The Order of Operations is Wrong

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  • Опубликовано: 15 окт 2024
  • Morally Wrong, that is...
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Комментарии • 20 тыс.

  • @haraldhey9210
    @haraldhey9210 5 лет назад +4720

    Never in my entire life I have heard that additions come before subtractions and multiplications come before divisions.

    • @Sir-Taco
      @Sir-Taco 5 лет назад +228

      Harald Hey It doesn’t.

    • @pendragon7600
      @pendragon7600 5 лет назад +213

      yup because it doesn't

    • @yrok244
      @yrok244 5 лет назад +422

      Yeah I can’t believe people actually thought that
      It should be PE(MD)(AS) to avoid confusion

    • @frostbyte000jm
      @frostbyte000jm 5 лет назад +230

      No one has, because it doesn't I agree with Yrok24. It should be PEMA. Because anyone that understands math knows Multiplication and Division are exactly the same thing (as is addition and subtraction).

    • @dashed0115
      @dashed0115 5 лет назад +45

      It's called BEDMAS

  • @Mswordx23
    @Mswordx23 9 лет назад +3748

    Minute Physics... PEMDAS does _not_ say do multiplication THEN division, or addition THEN subtraction. What PEMDAS teaches you is that multiplication and division have the same _priority_ (likewise for addition and subtraction). And for operations with the same priority and no brackets, you UNAMBIGUOUSLY CRUNCH THE NUMBERS FROM LEFT TO RIGHT.
    I ... I trusted you. I'm heartbroken...

    • @dallen3000
      @dallen3000 9 лет назад +319

      Mswordx23 thank you, either he misunderstood what he was taught, or his teacher taught him wrong

    • @ChrisGarrison72
      @ChrisGarrison72 9 лет назад +61

      Mswordx23 No Minute physics understands that, He shows you at 0:24 that you can get different answers by following PEMDAS.

    • @Mswordx23
      @Mswordx23 9 лет назад +424

      christian garrison No. There's only ONE answer if you follow it, and it's the answer you get if you go _left to right._ The answer 5 is wrong because he didn't go left to right, which is what PEMDAS teaches. At 0:12 he claims that it tells you whether to do addition before subtraction. He doesn't understand.

    • @AubreySalokaN
      @AubreySalokaN 9 лет назад +135

      Mswordx23 That may be what PEMDAS means, but there are plenty of Mathematics teachers that do a terrible job at conveying this, and simply tell their students to just follow the order that PEMDAS tells you to follow. I guess they assume that some future teacher will explain the whole multiplication&division and addition&subtraction rule to the kids, but this never actually happens. He's not getting PEMDAS wrong; he's simply telling us how it is (incorrectly) taught to the majority of America, thus why most Americans on Facebook will say "20÷2X5 = 2 idoits use pemdas"

    • @BOOBEXAMINER
      @BOOBEXAMINER 9 лет назад +80

      Mswordx23 I'm surprised he didn't know this or respond to this comment. Now I feel like all his other videos are wrong as well. :(

  • @Zeetrik
    @Zeetrik 5 лет назад +1116

    I mean I live in Spain and I was astounded when you said addition then subtraction, they have taught us that they have the same priority, and if there are two of them to go from left to right, always.
    So... im not so sure the rest of the world uses this like you said...

    • @fgvcosmic6752
      @fgvcosmic6752 4 года назад +160

      Nope - Not even his country uses it like this. This video doesnt really make any sense....

    • @roboknightt04
      @roboknightt04 4 года назад +17

      Yea i was taught the same as you

    • @dakotayupyupyup8377
      @dakotayupyupyup8377 4 года назад +33

      He learned it wrong

    • @mldag1678
      @mldag1678 4 года назад +11

      Same, we’re taught this is Sweden too

    • @michaelibrahim9275
      @michaelibrahim9275 4 года назад +56

      Even in the US they teach you the correct way. If you don’t listen in class and only remember PEMDAS, though, you will probably falsely believe that addition comes before subtraction

  • @jacobhall4655
    @jacobhall4655 4 года назад +187

    The one unspoken rule is that in Pemdas, it's more like PE(M,D)(A,S) where either M or D can come first between the two depending on which appears first when reading the equation left to right. For the 8-2+1, it's left to right, so you solve 8-2 which is 6, then +1. You wouldn't jump around and get 5 unless required by parenthesis.

    • @uknownada
      @uknownada Год назад +25

      That's not even an unspoken rule. Every time PEMDAS was taught to me, they mentioned that.

    • @thomasrosebrough9062
      @thomasrosebrough9062 Год назад +2

      Not exactly though. For 2+5-4, I would still in my head subtract the 4 first.

    • @jacobhall4655
      @jacobhall4655 Год назад +4

      @@thomasrosebrough9062 well yeah but thanks to the communitive property those are the same thing

    • @typecasto
      @typecasto Год назад +3

      that rule was very much spoken every time I've dealt with them

    • @Void_and_Colors
      @Void_and_Colors Год назад

      @@thomasrosebrough9062 you still going to get 3 due to number properties unless parenthesis is applied.

  • @43615
    @43615 5 лет назад +1939

    this is the first time i've heard of addition before subtraction
    they're equivalent and as such should be treated left to right

    • @jeremylee48
      @jeremylee48 4 года назад +64

      Gerry C That’s not the point. PEMDAS is only for kids. When you know math from grade 5 onward there’s no left and right.

    • @SteichenFamily
      @SteichenFamily 4 года назад +54

      If they're equivalent, then there's no need for left to right. Sum them in any order you want.

    • @masoodjalal1152
      @masoodjalal1152 4 года назад +41

      @@SteichenFamily Division and Multiplication have the same preceding. But if you don't go left to right you may get a very different answer.

    • @SteichenFamily
      @SteichenFamily 4 года назад +12

      According to PEMDAS multiplication and division have the same precedence, and are done left to right. But that's wrong. Multiplication can be done in any order, just like adding and subtracting. But division cannot. Division must be done in the correct order or the solution will change. Also, in most real world math multiplication should be done before division.

    • @masoodjalal1152
      @masoodjalal1152 4 года назад +29

      @@SteichenFamily no, not true. You cant do multiplication in any order if the operation contains division. 6 * 5 / 2 * 5. See, in this question you would get 3 if you do multiplication in any order. But the correct answer is 75, which is achieved by going left to right. See, addition and subtraction give same answer no matter what order you follow, but not true for multiplication or division. It is good practice to go left to right instead of solving parts of questions randomly.

  • @josephcrespo7822
    @josephcrespo7822 8 лет назад +2176

    wtf is PEMDAS
    in Soviet Russia it's VODKA

    • @komanderkane7098
      @komanderkane7098 8 лет назад +81

      Joseph Crespo in Canada its BEDMAS lol I'm so confused

    • @JackGmustdie
      @JackGmustdie 8 лет назад +52

      BIDMAS here :P

    • @MusicalInquisit
      @MusicalInquisit 8 лет назад +73

      For me is BODMAS

    • @starlightdemon2702
      @starlightdemon2702 8 лет назад +17

      I was taught BIDMAS

    • @MasterLond
      @MasterLond 8 лет назад +57

      BEDMAS and PEDMAS are the same thing. in PEDMAS the P stands for parenthesis (), in BEDMAS the B stands for Brackets....the first letter consistently represents a symbol of enclosure. You should all know by now the US always has to be "special".

  • @KaiHenningsen
    @KaiHenningsen 4 года назад +124

    I think I never heard of this bad order in my life, until now. I firmly remember the priority of addition and subtraction being the same, and so multiplication and division.

    • @irrelevant_noob
      @irrelevant_noob 2 года назад +4

      Except the phrasing "PEMDAS" doesn't capture that extra priority tweak you "remember". If it starts "P then E then ..." then anyone who doesn't fully remember the extra rules (or was never taught them) can easily infer it's also "M then D then A then S".

    • @MikehMike01
      @MikehMike01 Год назад

      Because this video is bs

    • @GoodNewsEveryone2999
      @GoodNewsEveryone2999 Год назад

      Same!

    • @MrGreensweightHist
      @MrGreensweightHist Год назад +3

      @@irrelevant_noob (can easily infer it's also "M then D then A then S".)
      Only if they weren't; paying attention the MANY times it is explains as not being like that.

    • @irrelevant_noob
      @irrelevant_noob Год назад +1

      @@MrGreensweightHist not paying attention to WHAT? Did you somehow miss my "or was never taught them" -- because i know i've never seen this before encountering it online.
      PS Fun fact: Another video on this topic, "How School made you Worse at Math" reveals that the American Physical Society Style and Notation Guide actually explicitly describes multiplication as a different and prior step before division. So it depends on who teaches you.

  • @dandymcgee
    @dandymcgee 10 лет назад +31

    Uhh.. P > E > MD > AS not P > E > M > D > A > S. Multiplication / division have the same operator precedence and are always evaluated left-to-right, as is also true for addition / subtraction.

    • @SSJ5Cloufiroth
      @SSJ5Cloufiroth 10 лет назад +2

      This. Standard OoO learned in the US says that "8 - 2 + 1" equals 7, not 5.

    • @AlphaDragonification
      @AlphaDragonification 10 лет назад

      SSJ5Cloufiroth No. The standard one equals 5. PEMDAS- the first thing you do is addition before subtraction in which turns it into 8 - 3 = 5

  • @huangjunwei7211
    @huangjunwei7211 6 лет назад +682

    i think it is more like: PE (MD) (AS) and always do it from left to right

    • @Kataris
      @Kataris 6 лет назад +22

      That's the way I also learned in in the 90s.

    • @huangjunwei7211
      @huangjunwei7211 6 лет назад +45

      Did this *actually correct* rule got lost overtime or something? I mean, in the country I live in, the teachers are still teaching the exact same thing with no modification whatsoever.

    • @derekmartin5340
      @derekmartin5340 6 лет назад +9

      thats the way I learned it in the 2010s

    • @lindayantilindayanti2585
      @lindayantilindayanti2585 6 лет назад +1

      And that’s not the way I learned it. You do it with an order. Numbers in brackets first, then multiply, then divide, then add, then subtract

    • @derekmartin5340
      @derekmartin5340 6 лет назад +2

      so where do you do exponent.

  • @robdoghd
    @robdoghd 8 лет назад +1318

    "But Mrs. Teacher! The internet man says it's the journey that counts!! !"
    "You just drew flowers all over your paper."
    "Yeah but the internet man said--"

    • @frtard
      @frtard 8 лет назад +107

      sounds like an xkcd comic

    • @thetechw1z
      @thetechw1z 7 лет назад +31

      BUT THE INTERNET MAN SAID...
      Teacher: Shut up.
      Student: INTEEERRRRNNETT MAN!!! NO!!!

    • @Titanic-wo6bq
      @Titanic-wo6bq 7 лет назад +7

      "YOU ARE DOODLING! BE QUIET!"

    • @spencerconnor9282
      @spencerconnor9282 7 лет назад +3

      robbie haha

    • @artemis6327
      @artemis6327 7 лет назад +2

      robbie
      Is it bad I do that during my actual classes

  • @H3Vtux
    @H3Vtux 3 года назад +36

    0:48 the PEMDAS order of operations method doesn't teach that. It teaches that Addition and Subtraction are on the same "tier" of importance, as are Multiplication and Division. Functionally it's P>E>M=D>A=S
    As far as your final conclusion, the method of placing any two pairings into brackets, PEMDAS doesn't interfere with it. If you want you can write the equation that way regardless of which order of operations you're using (as is required with some programming languages), PEMDAS simply lets you leave the brackets out in certain instances where convinient.
    I believe the reason PEMDAS was settled on is simply because even though it's arbitrarily chosen it makes the most sense. Multiplication is repeated additions, and exponents are repeated multiplications, so it makes sense they would have priority over each other for real world applications. The *most* logical would be to just do left to write unless parentheses are involved which i think is what you proposed, but it's not like PEMDAS makes no sense.

    • @barnieclarke7829
      @barnieclarke7829 2 года назад

      P.em.d.a.s makes a lot of sense .because it's not a mathematical law, it's just a guidance in the order of operations especially for fourth form students until they come to learn mathematics inside out as pro just like us. Videos like these are misleading to beginners in mathematics and should I say quite confusing and discouraging to the learning of mathematics which is so important in life's journey .

    • @okaro6595
      @okaro6595 4 месяца назад

      ​@@barnieclarke7829Just remember the thing not done stupid acronym.

  • @snakearm0028
    @snakearm0028 5 лет назад +960

    Wait. PEMDAS says the multiplication/division and addition/subtraction are on the same level but if there are both then read left to right.

    • @sayamqazi
      @sayamqazi 5 лет назад +25

      But I dont see that in the abbreviation. It clearly has M before D and A before S.

    • @breakaway7017
      @breakaway7017 5 лет назад +25

      Sayam Qazi and other people write it as BODMAD which mean the same thing

    •  5 лет назад +167

      Sayam Qazi “bUt I dOnT seE thAt iN tHe aBbreViaTioN” then you weren’t taught well, sorry. It is taught that they’re on the same level. At the same time I can understand that the acronym does not include “and” , but again that is taught.

    • @kusog3
      @kusog3 5 лет назад +37

      @ Sadly, there are teachers that teaches it this way, and arguing or correcting them is just gonna give you an F

    • @davidvelazquez9041
      @davidvelazquez9041 5 лет назад +3

      Watch the video again, please.

  • @fingerman4086
    @fingerman4086 9 лет назад +117

    We were never taught addition before subtraction, but rather both addition and subtraction in the order left to right in which they are presented

    • @PlanetCoolMinecraft
      @PlanetCoolMinecraft 9 лет назад +1

      Same here

    • @potatoman7895
      @potatoman7895 9 лет назад

      Actually, I was taught that not to long ago, about 4 years.

    • @Hemuro4ever
      @Hemuro4ever 9 лет назад +1

      +PotatoMan In the 8th grade I had a hick math teacher (moved out to the boonies for a year) try to teach the class that the order of operations was multiplication then division then addition then subtraction. Being a math geek I told her she was wrong in class, which she proceeded to try to talk her way out of. But then I grabbed the teaching book on her desk about it and proved her wrong. Then she got confused. She talked to the other 8th grade math teacher and conceded she was wrong about it. So yes, some ignorant teachers teach it that way. Even if they have the right way in front of them. It does happen.

  • @a2rhombus2
    @a2rhombus2 8 лет назад +1933

    I was always taught that multiplication and division were equal and so you did them left to right

  • @enbyennui
    @enbyennui 4 года назад +41

    Here in the UK we are taught BIDMAS (aka PEMDAS) but with the explicit caveat that division is really the same thing as multiplication and subtraction is the same thing as addition so those operations are paired in the list and you always perform them left to right

    • @fahrenheit2101
      @fahrenheit2101 3 года назад +19

      Not just the UK. Everywhere except Minute Physics' hometown I guess.

    • @enbyennui
      @enbyennui Год назад

      @@jewsrbad antisemitic username AND you're a physics crackpot huh? get a life

    • @MrGreensweightHist
      @MrGreensweightHist Год назад +3

      "with the explicit caveat that division is really the same thing as multiplication and subtraction is the same thing as addition"
      That is taught in the U.S. well, but there are students who ignore that part, just as there are in UK, I'm sure.

    • @TheBigGuyBillyBob
      @TheBigGuyBillyBob 9 месяцев назад +1

      What the heck does Bimdas stand for???

    • @enbyennui
      @enbyennui 9 месяцев назад

      @@TheBigGuyBillyBob brackets, indices (i.e. exponents/powers), then DMAS is the same.

  • @Vixikats
    @Vixikats 10 лет назад +113

    I don't think I've ever been told that addition comes before subtraction or anything weird like that. That isn't a US standard, that's just ridiculous and farcical.

    • @Vixikats
      @Vixikats 10 лет назад +1

      Yes, because in a sense, you're not subtracting a positive number, you're adding a negative. It's something easier to visualize why an equation of all addition/subtraction can be solved in any order. The standard Order of Operations is really just required when using anything above that, however.

    • @gameguy8101
      @gameguy8101 10 лет назад

      Ran, that does not work. Unless you change the subtraction into a added negative, it does not give the same answer. The associative property, if I'm correct, is the property that you can do a problem in any order you would want to if it is addition OR multiplication.

    • @Vixikats
      @Vixikats 10 лет назад +7

      gameguy8101
      But subtraction and negative addition is the same thing, just viewed from different perspectives. In fact, an equation like 7+3-4+9-8 could be simplified into 19-12=7 by lumping together the positive and negative values. 7+3+9 = 19 and -4+(-8) =12. Addition and Subtraction can be done together in any order, no matter what. Like I said, it's only when you tie in higher expressions like multiplication or exponents do you really have to worry about order of operations.

    • @Darticus42
      @Darticus42 10 лет назад +2

      I've been told that, but after learning from that same teacher that they were interchangeable. I mean, it doesn't make sense that one day she just teaches me all that they're interchangeable, then the next she yells at me for not strictly following the acronym. If I remember correctly I brought it up in class that they were interchangeable and she specifically told me that I can't switch up the ordering on PEMDAS... *sigh*
      But yes, that is not a part of the US Standard, it's just idiotic if teachers decide to contradict themselves day by day by day.

    • @TheDeluxe4O
      @TheDeluxe4O 5 лет назад

      Go on Instagram apparently it is😂

  • @durdleduc8520
    @durdleduc8520 6 лет назад +548

    90% of the comment section: “Oh, honey..”

    • @stephaniesummer2663
      @stephaniesummer2663 5 лет назад +54

      But seriously how did he get through school thinking this? My middle school teach would have instantly set him straight.

    • @IronicHavoc
      @IronicHavoc 5 лет назад +19

      @@stephaniesummer2663 Because He is correct in that once you get into hign enough levels of algebra it's often more effective to work with parentheses, commutivity, negative numbers etc., and so you rarely use pemdas. He probably forgot what exactly it was, only that at some point he stopped using it.
      I think there is a valid broader point to be made here but he incorrectly said the stuff about ambiguity and addition before subtraction, which really distracted from it. It's more just about how it's quicker to restructure equations, and often easier to visualize certain mathematical techniques, when operations dont have to be arranged a specific way left to right and instead are focused around groupings.
      What he probably should have discussed here is common core or something similar, which I think is what he was really advocating without realizing it. Which makes sense since lots of physicists/engineers/mathematicians often end up using methods like that instinctually when they do arithmetic.

    • @stephaniesummer2663
      @stephaniesummer2663 5 лет назад +6

      TacitIron Hav I do know PEMDAS is rarely used in higher level math, but I’m a little baffled that he thought every elementary math teacher taught it wrong. I do know the benefits of making math more flexible and I usually solve problems that way if I can.

    • @whenyou3939
      @whenyou3939 5 лет назад +5

      @@IronicHavoc That's why there is a show called "are you smarter than a fifth grader?" It's because adults forget things they learned in grades below 9.

    • @frostbyte000jm
      @frostbyte000jm 5 лет назад +3

      @@IronicHavoc I am taking Calculus 3, and we still use PEMA The D and S are useless since everyone knows Multiplication and Division are exactly the same thing (same thing with addition and subtraction).

  • @russell_rozenbaum
    @russell_rozenbaum 5 лет назад +613

    Somebody told this guy that he was wrong on one of those Instagram math problems, and he didn’t take it lightly.

    • @ZoroarkLover98
      @ZoroarkLover98 4 года назад +82

      In all honesty, those problems are usually made it so they are ambiguous using notation that I haven't seen any math teacher use

    • @manghariz2211
      @manghariz2211 4 года назад +21

      I can say people that really is good at math
      Really hate those instagram math question.
      They arent hard but i think the "only genius can ....." is what infuriate them.

    • @IceMetalPunk
      @IceMetalPunk 4 года назад +24

      @@manghariz2211 What infuriates me about them is when they are ambiguous, so they can have multiple answers that are all equally valid from the given information, but then they claim everyone is wrong unless they come up with the same answer the creator happened to choose. Like... if you want everyone to come up with the same answer, then give enough information to rule out all the others. If you leave it ambiguous, then don't tell people they're wrong when they give you a valid answer you weren't expecting.

    • @jarlfenrir
      @jarlfenrir 4 года назад +1

      @@IceMetalPunk But there is one set of rules everyone should understand and it's just pemdas. If there is no enough information, pemdas allows you to get rid of ambiguity. The problem is that everyone one apparently remembers how to apply pemdas in a slightly different way.
      I am aware that there are many convention for order of operations that differ greatly from pemdas, but pemdas is what everyone was taught in school, everyone should be aware and understand it and apply it where the problem seems to be a basic school problem (all those social media math problems looks like basic school problem, so I deduce pemdas is a way to go).

    • @IceMetalPunk
      @IceMetalPunk 4 года назад +5

      @@jarlfenrir Oh, I agree. I was talking more about those math "riddles" that usually use pictures or arbitrary symbols to fill in for variables, and say "only geniuses can solve the last equation". And then to actually solve it it's not math, but some trick of inference based on how the pictures are drawn that could mean many different things even if you notice it. Those are the ones that bother me.

  • @toastedclubsandwich
    @toastedclubsandwich 4 года назад +105

    Dear Henry,
    Bruh.
    Sincerely, everyone

  • @dafuq1933
    @dafuq1933 5 лет назад +2362

    "Badly taught order of operation is false" should have been the title of the video.
    If you learned it the correct way, there's only one answer possible.

    • @Vrism
      @Vrism 4 года назад +87

      Yes yes yes.... people would show me those math problems that are supposed to be unambiguous and they would never trick me and they were always angry as to why my answers were so consitent

    • @croissant7223
      @croissant7223 4 года назад +26

      It’s easier to learn if you colour code the order of operations I was always told brackets, indicies, division and multiplication, addition and subtraction.
      Dunno how it is in America cos im British

    • @brendanbarnard
      @brendanbarnard 4 года назад +24

      We learned it as you follow the order of operations, but you do it from left to right in groupings. So you do your multiplication and division in the same run, from left to right. Same with adition and subtractions.

    • @hassanakhtar7874
      @hassanakhtar7874 4 года назад +34

      If an answer can only be attained through order of operations you are doing very low level math that isnt that important anyways. Cough cough viral math problems

    • @morgankasper5227
      @morgankasper5227 4 года назад +4

      @@hassanakhtar7874 like 2+2=4

  • @Sloppy_McFloppy
    @Sloppy_McFloppy 11 лет назад +103

    What people don't understand is that you do brackets first, then exponents, then you do both multiplication AND division in what order they are in from left to right, then the same thing with adding and subtracting...

    • @ZephWraen
      @ZephWraen 11 лет назад +11

      That's how I was taught and I'm from the US. I find it weird whenever someone says they were taught to always add before subtract and always multiply before you divide. Maybe my algebra teacher was just a badass and taught us the underlying mechanics a little early.
      Because, as is stated in the video, subtraction IS still addition, just adding a negative, and division IS still multiplication, just with a fraction.
      So it would make no sense why you would always add before you subtract, etc

    • @Sloppy_McFloppy
      @Sloppy_McFloppy 11 лет назад +11

      I was actually taught BEDMAS which is basically the same thing except instead of "parentheses", it's brackets, and multiplication and division are swapped, only proving my point that the order of multiplication and division does not matter.(as well as "+" & "-")

    • @Xenxe777
      @Xenxe777 11 лет назад

      You know? This would have been really great to go over more than once in school. Im sure this fact was said at one point but never really elaborated on. I now know why randomly I would get an answer wrong in highschool.

    • @IHateUniqueUsernames
      @IHateUniqueUsernames 11 лет назад

      Xenxe I think it would be better if the basic concept of the operators were actually thought rather than the function/result of the operators. In many cases the basic concept of addition and subtraction are provided when first taught, but not revisited later, particularly not when order/sequence became important in a string of operations. Otherwise 3-3 = 3+(-3) becomes clear. So would 3x3 = 3+3+3 or 3^3 = 3x3x3 = 3+3+3+3+3+3+3+3+3... any operator.
      It would sound simple and obvious to you now, because you know this. But to a child learning it, it is really valuable and powerful information. The idea is to present everything in addition (division can be done this way as well) as the common denominator (you do not want to answer why 1+1=2, so it is very recommended to not go further :D ).
      Not a quick way to learn/do maths? Think again. After a few exercises, the student will soon learn to shortcut the process by doing the actual operation, just because it is quicker than breaking it down to so many additions - and the student wants to finish it faster. But by then, they would have internalized what PEMDAS tries to do, thereby rendering PEMDAS not only unnecessary, it does not create confusion nor what you have experienced.

    • @brianhu6277
      @brianhu6277 11 лет назад

      Agree

  • @chromosoze
    @chromosoze 6 лет назад +1093

    "Addition before subtraction"
    *facepalm*
    Its addition AND subtraction
    hey guys thanks for the likes on such a puny comment,.

    • @cereiul
      @cereiul 4 года назад +70

      Yeah, you solve then from left-to-right order

    • @Knee-Lew
      @Knee-Lew 4 года назад +73

      That's what I thought, too.
      Parentheses
      Exponent
      Multiplication and Division
      Addition and Subtraction
      And orders are from left to right, as you said.

    • @adamzalevich750
      @adamzalevich750 4 года назад +4

      You read it like a book, solving left to right

    • @albinocake
      @albinocake 4 года назад +3

      Agreed

    • @totophotoPersonal
      @totophotoPersonal 4 года назад +2

      Agreed

  • @parktamaroon226
    @parktamaroon226 6 лет назад +569

    PEMDAS needs parentheses: PE(MD)(AS)

    • @punkducky69
      @punkducky69 6 лет назад +31

      According to this guy, it'd look more like (P(E(MD(AS)))).

    • @ryleywilliams1534
      @ryleywilliams1534 6 лет назад +59

      punkducky69 actually it would have the P as the innermost parentheses. ((((P)E)MD)AS)

    • @luisito9943
      @luisito9943 6 лет назад +7

      This is actually the real pemdas cuz teachers are stupid

    • @cigmorfil4101
      @cigmorfil4101 6 лет назад +17

      Kyle Miller roots are x^(1/...) so they're already covered

    • @birthsonbluebell3654
      @birthsonbluebell3654 6 лет назад +1

      What would Parentheses mean? This statement is a paradox.

  • @8stormy5
    @8stormy5 2 года назад +12

    To counteract all the personal anecdotes here, I was indeed taught that multiplication comes before division and that addition comes before subtraction by three separate teachers before my sixth grade math teacher told us PEMDAS was wrong and if we wanted to use it to use PE(MD)(AS) from left to right instead.

    • @MrGreensweightHist
      @MrGreensweightHist Год назад +3

      PEMDAS is, and has always been PE(MD)(AS)
      Sorry your earlier teachers didn't explain that well.
      Early grade teachers are required to know a little about a lot of subjects, but it makes them less ideal for getting any one particular subject quite right.

    • @adrianmcbride1666
      @adrianmcbride1666 4 месяца назад

      BTW mine specifically told us that it should not matter what order you solve bodmas so long as you do not cross orders.
      BTW for 6/3/3 I get 2/3
      6/1×1/3×1/3=6/9=2/3. Do all multiplication and division simultaneously and do not simplyfy till you have reduced to a single fraction if possible.

  • @topanteon
    @topanteon 9 лет назад +32

    I love it how people are arguing that the guy doesn't know maths even though he's finished college that required him to do maths. On another note: I love it how people fucking fail at understanding what the video is actually about.

    • @chopinbloc
      @chopinbloc 9 лет назад +7

      Yeah, many of us also graduated from college that required us to do our own "maths." He got it wrong.

    • @stevensantos8975
      @stevensantos8975 9 лет назад +1

      ***** But he doesn't ever use it... So what's the point of using a 6 step rule for algebra when you can just learn math in a proper way, and then do whatever you want as long as you get the correct answer? (obviously I don't mean WHATEVER you want but that you follow the rules of notation). He doesn't have a use for the "rule" and he's really good at math judging from his knowledge of physics. Having a major doesn't require use of PEMDAS.

    • @topanteon
      @topanteon 9 лет назад +3

      ***** I think you simply missed the point of this video. The video says that the order of operations is "morally" wrong.

    • @Patrick_Bard
      @Patrick_Bard 9 лет назад +1

      Derfoklishe Finally someone with enlightened mind. Thank you for making me think everybody here is ignorant.

    • @liljos123
      @liljos123 9 лет назад +1

      +Derfoklishe I at first I felt alone, but now someone is on my side about this shit.

  • @blanmorrison1794
    @blanmorrison1794 7 лет назад +197

    0:52 When it says "AS," it doesn't mean" addition before subtraction, that makes no sense, because (technically) there is no such thing as subtraction. It just means "add and subtract from left to right."

    • @Cricketot1
      @Cricketot1 7 лет назад +23

      This; all order of operations teaching will say 8-2+1=7. If it doesn't or didn't then it is 100% incorrect and the person teaching it taught you wrong.

    • @blanmorrison1794
      @blanmorrison1794 7 лет назад +6

      I agree it is seven. I don't know what you're trying to get at here.

    • @Tyw7
      @Tyw7 7 лет назад +4

      It's always addition - subtraction from left to right.

    • @olivermorrison7127
      @olivermorrison7127 7 лет назад +2

      Blab Morrison
      "It doesn't mean addition before subtraction"
      It does on the BBC Bitesize page. A well respected revision tool used by almost all secondary schools in the England.
      www.bbc.co.uk/education/guides/zsnycdm/revision
      Children ARE being taught these rules and it's confusing all of the mathematics they try to learn there after.
      I don't think people realise what a problem this is. If I had been in school the day they taught this (I happened to be ill that day) I think I would have struggled with maths a lot more

    • @b1rd1e81
      @b1rd1e81 7 лет назад

      Why can't we just add +ve terms and add -ve terms and then subtract -ve total from +ve total. easy right?

  • @El_Pato
    @El_Pato 5 лет назад +650

    *p* lease *e* nd *m* y *d* epression *a* nd *s* uffering

    • @person8064
      @person8064 4 года назад +21

      Roses are red
      Violets are blue
      Existence is pain
      I just wanna die
      - Random meme I found

    • @morningglorymoth
      @morningglorymoth 4 года назад +8

      I like this better than the actual pneumonic.

    • @Hyper_TheOne
      @Hyper_TheOne 4 года назад +2

      its also spelled like that exactly

    • @ilovejimmy2012
      @ilovejimmy2012 4 года назад +3

      What if you got a friend

    • @sidewalk__
      @sidewalk__ 4 года назад +1

      Jazzy S *Mnemonic

  • @studypurposeonly69
    @studypurposeonly69 Год назад +4

    Am I the only one who thinks this video completely makes sense? All I see here is "left to right" comments who didn't get what he is trying to say in the video

    • @GanonTEK
      @GanonTEK Год назад +1

      It's an excellent video.
      Understanding grouping opens up so many more ways to simplify an expression than the literal order of operations does.

    • @mr.getrighhttt3433
      @mr.getrighhttt3433 Месяц назад

      I think it’s a great video. Only those who didn’t take higher level math classes think it’s dumb.

  • @Ava-mo1ij
    @Ava-mo1ij 8 лет назад +380

    0:53 no they dont.. We learn that whatever order addition or subtraction comes first, we do first, therefore 8-2+1 is 7, not 5....

    • @Ava-mo1ij
      @Ava-mo1ij 8 лет назад +33

      and high school math courses teach distributive property... we learn order of operations first in elementary or middle school...... so dont think we're dumb like that or teachers keep us in some bubble. we DO learn different ways to do algebra, just later on in high school.

    • @CLAX1337
      @CLAX1337 8 лет назад +19

      +Aboorvaa the way you get 5 is by distributing the - for no reason at all, lol
      8 - 2 + 1 -> 8 - (2 + 1) -> 8 - 2 - 1 = 5
      When really you're adding 1 to -2, giving you 8 - 1 = 7.
      Adding 1 to -2 means you should be subtracting less, giving you a greater number than if you had just subtracted 2 (6 < 7). PEMDAS accounts for this, like you said above ^
      I don't know why Minutephysics randomly distributed the - as if that's what PEMDAS says to do :/

    • @12jordanlewis23
      @12jordanlewis23 8 лет назад +4

      +Aboorvaa i was going to say that, i never learned that multiplication comes before division, or addition comes before subtraction

    • @itzpyrex-vlogsreactions6366
      @itzpyrex-vlogsreactions6366 8 лет назад

      Your correct, we learn it like p,e,[md],[as] Know as multiplication and division and equal, same with addition and subtraction. so when you see division then multiplication, just go in order, then do addition and subtraction in order also to get a answer, Min solved it like [8-(2+1)] = 5, when really its [(8-2)+1] = 7..... Kids are going to take over at some point xP

    • @jackmedrek4373
      @jackmedrek4373 8 лет назад

      +Abby S yeah addition and subtraction can be flipped, just like multiplication and divsion

  • @iweegouldyi8466
    @iweegouldyi8466 8 лет назад +448

    Also, in Scotland we are taught to
    Go left to right in most cases
    Then
    Brackets
    Powers
    Multiplication / division (once again move left to right)
    Add / subtract (left to right)
    Really is not a difficult idea to follow is it?

    • @Name-km6bx
      @Name-km6bx 8 лет назад +27

      iWeeGouldyi Yeah, it is (left to right on equal ranks):
      1 (p)arentheses
      2 (e)xponents
      3 (m)ultiplication/(d)ivision
      4 (a)dd (s)ubtract
      Or, pe(md)(as)

    • @iweegouldyi8466
      @iweegouldyi8466 8 лет назад +27

      Yep, i don't see what the fuss is about. It's a simple system really

    • @TheCobyMagic0
      @TheCobyMagic0 8 лет назад +29

      The point isn't about how easy the system is to learn, clearly it is simple to learn since it is taught in elementary schools everywhere. The point is that there need not be such a system if you understand the underlying principles. This video is lamenting the fact that the education system tends to teach students how to "do math" as a mechanical process instead of teaching them how math actually works.

    • @iweegouldyi8466
      @iweegouldyi8466 8 лет назад +12

      I can agree with you there, some teachers throw an equation at you without telling you how it works. Which i feel is a complete and utter fuck up in most cases. I struggle to apply the correct equations if i'm not taught what the equation is actually doing for us. Differentiation, Curve Sketching and Integration come straight to mind

    • @pringle-man
      @pringle-man 7 лет назад +11

      iWeeGouldyi it’s that way in America too, Minute Physics either changes it for a better video or just didn’t understand what it actually meant

  • @LM11116
    @LM11116 7 лет назад +259

    In school they specifically teach you that when you have multiple of the same or similar operations (e.g. 6/3/3 or 7/3*2) you go from left to right (also order of operations puts M before D and A before S just because they have to put it in *some* order. they always specify that multiplication and division have the same priority and addition and subtraction have the same priority.)

    • @ryledra6372
      @ryledra6372 6 лет назад +7

      Yes, then they teach you how to write it with less ambiguity...
      From A Level maths, I'd see 6/3/3 = 6... I would tend to see it as a 3 tiered fraction written as (6/3)/3 [rewritten as (6x3)/3] or 6/(3/3) [rewritten as 6/1]. Rather than the 2/3 suggested by BIDMAS (or which ever form you most wish to look at).
      At A Level you would be corrected from writing 7/3*2 and be told to write it as 7/(3*2) or (2*7)/3 dependant on what you meant; and this is more the point of his video, the answer's given using Orders of Operations can be open to interpretation if you have a deeper understanding of fundamental mathematics.

    • @travonpough5626
      @travonpough5626 6 лет назад

      Thank you

    • @travonpough5626
      @travonpough5626 6 лет назад +2

      These guys are stupid

    • @orealis1272
      @orealis1272 6 лет назад +1

      I learned this in my first school but when I changed school the people were just I guess they weren't thought that or something.... Like *sigh* It was fifth grade and they didn't know PEMDAS!!??!?!?

    • @Tfin
      @Tfin 6 лет назад +7

      No, they DON'T "always specify" that those have the same priority. In fact, our tests' problems were constructed to never conflict with the strict P>E>M>D>A>S order of operations, so we were left not knowing that 5 - 3 + 2 = 4 until a couple years later. Instead we knew only that 5 + 2 - 3 = 4.

  • @fritzzz1372
    @fritzzz1372 3 года назад +4

    I'm very disappointed by the comment section. The entire point of the video is that the order of operations is not what math is about, but basically every comment conplains about how minutephysics misunderstood the PEMDAS rule. Have you even listened to him? That's not what math is about. And yes, he misunderstood it, but this is the exact problem with PEMDAS: the letters say that multiplication comes before division and addition comes before subtraction, so a teacher has to tell you you how it really works. The rule is inaccurate and has to be corrected by a teacher. Why would we use such a stupid and also technically wrong letter combination as a mnemonic device when that's not even what math class should be about?

  • @peterpeterson1882
    @peterpeterson1882 10 лет назад +36

    Please do not target the US educational system for teaching PEMDAS. As others have said, either you have misinterpreted what it means, or the entire US educational system has. PEMDAS does not give priority to Multiplication over Division nor Addition over Subtraction. As bad as the US educational system is, it's not THAT bad.

    • @Darticus42
      @Darticus42 10 лет назад +3

      Oh, I had a math teacher in 6th grade who was THAT bad. After learning (from her no less) that they were interchangeable, I argued over one of my answers because she counted me wrong for not strictly following the order of PEMDAS. It was not a problem of clarification, I explained to her many times in many different ways that they were interchangeable, she just decided to ignore the rule that those operations are interchangeable. Granted, the US Educational System is not generally that bad overall, though there are a few imbecilic teachers out there... I wouldn't be surprised if some of the teachers in the US Educational system "forgot" to teach that some operations are interchangeable. Then there was that time our whole class took 20 minutes to teach her how to say "crayon"...

    • @peterpeterson1882
      @peterpeterson1882 10 лет назад +1

      Darticus the Great Haha, my god that is bad. What state did you live in? And what is it about the pronunciation "Crayon" that gets people so mad? One time a big argument broke out in my family during a reunion over whether to pronounce "Crayon" as \'kran\, \ˈkrā-än\, or \ˈkrā-ən\. Is she one of the people who pronounce Crayon as "Crown"? xD

    • @MikehMike01
      @MikehMike01 Год назад +1

      this video is a big lie

  • @roccass59
    @roccass59 8 лет назад +196

    I was taught that operations of the same rank (subtraction and addition, multiplication and division) were in a sort of queue. For example:
    8-2+1
    We subtract 2 from 8
    6+1
    Then we add the rest
    7
    What kind of education system would teach you that 8-2+1=5?! That is only true if 2+1 is surrounded by paranthesis:
    8-2+1=7
    8-(2+1) =5

    • @DanielRamos-wo2rq
      @DanielRamos-wo2rq 8 лет назад +7

      +Alexandra Roceanu I think their problem is that they thing you literally have to follow everything in the "PEMDAS" rule. They are not taught that Multiplication and Division, and Addition and Subtraction go hand in hand.
      As a result, they think addition must always be first.

    • @pascalos99
      @pascalos99 8 лет назад +11

      +Daniel Ramos who is taught to not do those hand in hand? Is the rule different in amarican education? if so, that's dumb.

    • @ChaosPod
      @ChaosPod 8 лет назад +4

      No, of course the rule isn't different in the USA. My guess is that Math Teachers over there emphasize strongly on PEMDAS without strongly emphasizing that M/D and A/S are of equal rank. So you end up with students who know PEMDAS but don't understand that M/D and A/S are of equal rank.

    • @Willow4526
      @Willow4526 8 лет назад

      don't know what this pemdas is but it sounds like our bimdas XD lol. unless it wasn't taught very well to us or the teacher at one stage, my classes were always taught that it was in order for bimdas (pemdas) multiplication then division, addition then subtraction.
      could be as i stated it may of not been taught to us/other people with emphasis. but this explains why that system always seamed retarded to me, mainly bcos i was most likely taught wrong XP

    • @pascalos99
      @pascalos99 8 лет назад

      +ChaosPod If you learned PEMDAS, you learned it in the US, since it's written in english. Also it has 6 letters, when you separate 4 operations. The rule officialy taught where I live has the operations addition and subtraction as one and the same for multiplication and devision. So actually, it is the US's fault, or at least the english education System camera up with it, either way PEMDAS is intirely wrong!

  • @jamesfoley2759
    @jamesfoley2759 7 лет назад +154

    Are you telling me that I should not excuse my dear Aunt Sally??

    • @blakebowman3214
      @blakebowman3214 6 лет назад +3

      James Foley please

    • @repurify1144
      @repurify1144 6 лет назад

      No

    • @radioactive_baby
      @radioactive_baby 6 лет назад +3

      My friends and I said
      Please
      Enjoy
      My
      Darn
      Awesome
      Spaghetti

    • @xpertdre2955
      @xpertdre2955 6 лет назад

      Shawn Elliott what does that have to do with order of operations?

    • @deusexaethera
      @deusexaethera 6 лет назад

      It's an alternate mnemonic device, XpertDre.

  • @raphaelhamilton3526
    @raphaelhamilton3526 Год назад +2

    In the UK (or at least at my school), we are taught that × and ÷ are equal and so should be left to right, as are + and -.

  • @hahnchen6608
    @hahnchen6608 8 лет назад +679

    Okay, I went to an elementary public school and they taught me
    P
    E
    MD left to right
    AS left to right

    • @viktorpanum85
      @viktorpanum85 8 лет назад +21

      LAURIE Q. I also believe that is correct

    • @yamilegarcia1820
      @yamilegarcia1820 8 лет назад +7

      they did the same for me too but i am a fifth grader btw

    • @thekeithchannel
      @thekeithchannel 8 лет назад +8

      That's where the ambiguity comes in because try doing 6 ÷ 2(1+2) = ?
      Pemdas gives you 9
      Old convention gives you 1

    • @aaronzahradnik3686
      @aaronzahradnik3686 8 лет назад +25

      This is why fractional notation for division is better than the divide symbol. There's no ambiguity as to which terms are in the numerator or denominator

    • @thekeithchannel
      @thekeithchannel 8 лет назад

      Aaron Zahradnik I would say that I agree but even in fractional form, there still remains an ambiguity due to the order of operations.
      One could still argue that 1+2/(x+2) = 1/(x+2) + 2 because division holds priority over addition/subtraction.

  • @ariztrad
    @ariztrad 7 лет назад +154

    ? i was taught that it was like
    P
    E
    MD
    AS

    • @FacePalm629
      @FacePalm629 6 лет назад +13

      yes you do the mutltiplication or division in the equation as they are chronologically displayed, not just multiplucation first then division so that's why I hate all teachers now for not having standardized this

    • @kylelambert8322
      @kylelambert8322 6 лет назад +2

      This.

    • @audreywhalen5141
      @audreywhalen5141 6 лет назад

      Ariz Trad I was taught both in two different states. He probably lived somewhere that taught it
      P
      E
      M
      D
      A
      S
      Instead of
      P
      E
      MD
      AS

    • @scottbelanger4546
      @scottbelanger4546 6 лет назад

      Yes.
      Order or operations is correct. Its those who think that multiplication is before or after division who are wrong. They happen at the same time and use left to right to determine order.
      B,E,MD,AS

  • @real.sugarcone
    @real.sugarcone 7 лет назад +573

    minutephysics, if this was how you learned the order of operations, you must've had a tough time in math class.

    • @zapxcero
      @zapxcero 6 лет назад +5

      lmao

    • @RKBock
      @RKBock 6 лет назад +2

      which exactly? if he learned it with pedmas, or if he learned math?

    • @davidrojas9668
      @davidrojas9668 6 лет назад +62

      No, his version of PEMDAS is completely wrong.

    • @lezhilo772
      @lezhilo772 6 лет назад +11

      Which is good, because PEMDAS removes all the principles and beauty behind arithmetic. Who cares about PEMDAS and whether someone has learned it well and getting right answers in tests when you can do so much more?

    • @ryledra6372
      @ryledra6372 6 лет назад +3

      He did point out that multiplication and division were basically the same operation and addition and subtraction were as well...

  • @Rayzan1000
    @Rayzan1000 3 года назад +30

    The misconception about PEMDAS and "left to right" is that people believe it to be actual 'rules' for math, when they're in actuality just 'tools' for math.
    If you understand how the operations work, you don't need any of it. You can do calculations in any order you like (left to right, right to left, centre right left) - it's all about understanding how the operations work.
    If you are getting different answers based on the order you do the operations, then you are doing something wrong - plain and simple!
    For example: a common misconception is how division works. When you divide by a component (i.e. x) you are actually multiplying by 1/x, which is something you HAVE to keep in mind if you don't go left to right. The reason I mention division is because a lot of people in the comment section are misunderstanding how division works.

    • @themimsy
      @themimsy 2 года назад

      Order of operations are important. If you’re doing the same problem as someone else but they follow order of operations and you don’t and your get different answers, your answer is incorrect.

    • @RealMesaMike
      @RealMesaMike 2 года назад

      @@themimsy Certainly getting the right answer is important. The point is that it's just not necessary to strictly follow "order of operations" (particularly the "left-to-right" nonsense) to get the right answer.

    • @Rayzan1000
      @Rayzan1000 2 года назад +3

      @@themimsy The order does not matter as long as you understand how the operations work.
      For example:
      2 x (1 + 4) = 2 x 5 = 10
      Or
      2 x (1 + 4) = 2 + 8 = 10
      See, it doesn't matter whether I multiply first or solve the parenthesis first.

    • @schwarzerritter5724
      @schwarzerritter5724 11 месяцев назад

      Even if you are doing everything right, there are still some ambiguous cases with hidden operators and signs that mean different things.
      For example, what is 4 / 2(2 + 2)? You could mean 4 / (2(2 + 2)) or you could mean 4 / 2 * (2 + 2). Or what about -3². It could mean (-3)² or -(3²).
      You can probably show me a math website that solves these cases, but I can show you a math website that says different.

  • @betohax
    @betohax 8 лет назад +433

    It's not PEMDAS. It's PE (M or D, work left to right) (A or S, work left to right)

    • @Klatski
      @Klatski 8 лет назад +12

      I dunno, that doesn't roll off the tongue as easily...

    • @betohax
      @betohax 8 лет назад +1

      Klaty
      lol

    • @enjoyfanta9382
      @enjoyfanta9382 8 лет назад +10

      +beto hax The 'left to right' rule is crap. You can still perform the expression
      8-2+1 right to left as long as you understand that you must perform it
      as 1-2+8
      left to right: 8-2+1
      =6+1
      =7
      right to left: 1-2+8
      =(-1)+8
      =7

    • @KnekoKcat
      @KnekoKcat 8 лет назад

      Exactly what I was thinking'. Yes, that is, in fact, grammatically correct.

    • @KnekoKcat
      @KnekoKcat 8 лет назад +2

      P
      E
      MD
      As

  • @rockoman100
    @rockoman100 11 лет назад +122

    The MD in PEMDAS does not mean "Multiplication THEN division", it means "Multiplication AND division from left to right". Same thing goes for the AS.
    Sorry minutephysics, this one is weak.

    • @DaBananaboat
      @DaBananaboat 11 лет назад +3

      Exactly how I learned it in high school, after being confused from it by being taught something completely different in middle school.

    • @chao1111
      @chao1111 11 лет назад +2

      Yeah, paused at 20 seconds just to see if anyone stated. What on earth were they thinking?

    • @JuliaSudusky
      @JuliaSudusky 11 лет назад +2

      yeah, that's how i learned it in middle school. makes sense, why else would everyone get taught that

    • @TwilightWolfi
      @TwilightWolfi 11 лет назад +3

      I learnt that as well. It's not weak, it's just not very well-worded. I get what he was trying to get across, but it could have been explained better.

    • @matteo-ciaramitaro
      @matteo-ciaramitaro 11 лет назад

      It should be GEMS (Grouping symbols, Exponents, Multiplication and Division, and Subtraction and Addition)

  • @ColdFuse96
    @ColdFuse96 5 лет назад +857

    Dear Minute Physics
    *NO, YOU’RE WRONG!!!!*
    ~ The comments section.

    • @69elchupacabra69
      @69elchupacabra69 4 года назад +92

      Perhaps he IS wrong.
      He tried to look smart by correcting an issue that isn't there in the first place.
      I'm from a third world country and even our schools aren't this bad

    • @ballroomdancer2010
      @ballroomdancer2010 4 года назад +29

      @@69elchupacabra69 true. Except there are still too many people who have gotten confused with the order of operations because of the acronym PEMDAS. They remember what each letter stands for but forget how to actually use it properly. I know a 30 year old who doesn't remember and i consistantly have to remind her and correct her on it. Her mom who is in her 50s also does not remember how to use it properly.

    • @69elchupacabra69
      @69elchupacabra69 4 года назад +29

      @@ballroomdancer2010 in that case PEMDAS is not wrong, it's the people.
      Otherwise that's like saying long division is wrong because there are people that get long division wrong. Heck even people do simple addition wrong.

    • @spacezeppeli7358
      @spacezeppeli7358 4 года назад +4

      Sore wa chigau yo!

    • @HeadCannon19
      @HeadCannon19 4 года назад +11

      Luciano Martinez I mean, he is wrong; multiplication and division have the same priority, same with addition and subtraction, and for operations with the same priority you always go left to right so his examples at the beginning weren’t ambiguous in the slightest, and his example at 0:46 is just completely incorrect based on how PEMDAS actually works

  • @SixNineFourTwenty
    @SixNineFourTwenty 4 года назад +27

    "It turns humans into robots"
    School: someone called?

    • @n0nenone
      @n0nenone 4 года назад +1

      This was the motive of the vdo still everyone missed lol

  • @imikla
    @imikla 7 лет назад +199

    I love your channel, but you have this one wrong. This is not how it it is taught in the US. It is taught (P)(E)(MD)(AS) left-to-right by group, applied left to right and recursively within parentheses. For example, in ((8-2+1)+1)-2+1, you would apply (P)(E)(MD)(AS) left-to-right to the numbers in the inner most group resulting in (7+1)-2+1 = 8-2+1 = 6+1 = 7). Now people do constantly misremember that (MD) is to be applied together left-to-right and (AS) left-to-right together, and do get wrong answers, but that is their mistake, not how it is taught.

    • @ryledra6372
      @ryledra6372 6 лет назад +5

      He did also state that subtraction is really just the addition of a negative number, and that division is multiplication with fractions...

    • @XPimKossibleX
      @XPimKossibleX 6 лет назад

      Yep, I learnt it as bedmas. (B for brackets, why call it parentheses?)

    • @hiimshort
      @hiimshort 6 лет назад +7

      michael benzur because brackets are an entirely separate thing and have their own meaning.

    • @XPimKossibleX
      @XPimKossibleX 6 лет назад

      so y'all don't even say brackets (half the syllables) when you mean the maths symbol?

    • @knightsljx
      @knightsljx 6 лет назад +3

      You miss the point of the video. As the video states, PEMDAS is just one of the methods, and the way USA teaches. The problem comes when people who are taught different methods believe their's is the ONLY method. The UK teaches BODMAS (Brackets, Orders, Division and Multiplication, Addition and Subtraction). Notice that multiplication and division is ranked the "same" in hierarchy. So the British performs the 2 operations from left to right, not giving priority to multiplication. No one is wrong, but you're just communicating using different language.
      And as the video recommends, use parentheses is avoid ambiguity.

  • @YuriTardid
    @YuriTardid 10 лет назад +24

    I was taught that multiplication doesn't necessarily come before division, and that addition doesn't necessarily come before subtraction, rather, you do which ever one comes first in the group reading left to right, such as PE(MD)(AS); so 6/2*5 would be read left to right naturally and come out to 15 (division "first")rather than 0.6 (multiplication first). The same would be said in 3-2*6+2; reading left to right, the answer would be -7 (subtraction "first")rather than -11 (multiplication first).

  • @RyedaleAirsoft
    @RyedaleAirsoft 10 лет назад +10

    Brackets > Indices > Multiply/Divide > Add/Subtract

  • @BeholderThe1st
    @BeholderThe1st Год назад +1

    All of these PEMDAS videos ignore implicit multiplication by juxtaposition. When the multiplication sign is missing, the implication is that the multiplication is a common factor of everything inside the brackets, the brackets around the term are implied, see the AMS style guide.

  • @MotorsportsX
    @MotorsportsX 8 лет назад +61

    pemdas is not wrong.. Your understanding. (apparently the way you were taught) is wrong. M&D should be looked at as a group as well as A&S. So PEMDAS should really be PE(MD)(AS). You do multiply & divide, left to right no matter which operation it is. Of course once you learn math you instinctively know what to do and when.

    • @renardmigrant
      @renardmigrant 8 лет назад +2

      +MotorsportsX 6/6/3 is still ambiguous. It's not wrong so much as it's a norm not a mathematical truth and it sometimes gives more than one answer.

    • @MotorsportsX
      @MotorsportsX 8 лет назад +12

      +Martin Gardner no.. It's definitely not. It's understood you work the problem left to right. That's part of the universal process of doing math. This is a non issue.

    • @renardmigrant
      @renardmigrant 8 лет назад +2

      MotorsportsX you never stated that in your original post. And it's far from universal, that's entirely the problem. This is a convention, not a truth.

    • @MotorsportsX
      @MotorsportsX 8 лет назад +3

      +Martin Gardner then go ask any math professor anywhere how to work a math problem. I know you worked hard on you little video here but that doesn't make you right dude.

    • @renardmigrant
      @renardmigrant 8 лет назад +3

      It's not my video (which I feel like is a compliment, albeit an inaccurate one), but, no, PEMDAS is not universal, we don't have it in the UK for example and other people are commenting on this video with other system. That's a thing with a convention, people are free to come up with other conventions if they like.

  • @MaxwellTornado
    @MaxwellTornado 9 лет назад +163

    What the?! Americans gave addition and subtraction separate layers? What is wrong with you? In Hungary, we have: 1. Brackets
    2. Exponents
    3. Multiplication/Division
    4. Addition/Subtraction
    5. Answer.
    This is solved by the simple rule of ALWAYS GO FROM LET TO RIGHT, unless the order of operation is in effect.

    • @YouSunkMyFishy
      @YouSunkMyFishy 9 лет назад +68

      We follow the same rule in America. The people who made this video are idiots. I love most of their work, but... this is just stupid. We learn PE(MD)(AS), the same as BE(DM)(AS).
      1. Parentheses (Brackets),
      2. Exponents,
      3. Multiplication/Division from left to right,
      4. Addition/Subtraction from left to right.
      Seriously, this video needs to be removed. I can't understand how it has ANY positive votes.

    • @AdamBrackney
      @AdamBrackney 9 лет назад +18

      You Sunk My Fishy Sadly I have to agree with you. I love these videos, but this one solves a problem that never existed. You described what was taught in my school and my mother is a grade school teacher that teaches the same thing.

    • @MaxwellTornado
      @MaxwellTornado 9 лет назад +11

      You Sunk My Fishy Adam Brackney That's probably the best response i ever got to a hate comments. Thanks for being rational.

    • @YouSunkMyFishy
      @YouSunkMyFishy 9 лет назад +7

      ***** That is... quite possibly the saddest information anyone has ever shared with me.

    • @trulyUnAssuming
      @trulyUnAssuming 9 лет назад +1

      ***** Maybe the word PEMDAS is the wrong way of teaching people the order of math operations since it seems so misleading. I always thought about the hirarchy that way:
      5^3 = 5*5*5 = 5*(5+5+5+5+5) = (5+5+5+5+5)+(5+5+5+5+5)+(5+5+5+5+5)+(5+5+5+5+5)+(5+5+5+5+5)
      So oviously the brackets first - then the most complex operations beeing Exponents/Roots, after that the less complex operations - continue in that order. And the complex operations are just the short notation of a chain of more simply operations. But if you need it you can think of it as the chain again.
      Because of that I never learned anything besides the multiplication table until 10*10, like the square numbers until 25 or things like that, my teacher wanted me to^^ If I have to multiply 16^2 without a calculator it is 16*(10+6)=160+6*(10+6)=160+60+36=256.
      That's the beauty of math - you don't need a clue of anything and can still get a good grade. Only a small set of rules - go play around.
      So if the acronym PEDMAS dosn't help people understand that concept - I don't know why anyone would use it. I don't think we have that problem here in Germany - but maybe I just didn't recognize it...

  • @connorpaulsen4414
    @connorpaulsen4414 8 лет назад +341

    You clearly are missing a massive part of the Order of Operations.

    • @connorpaulsen4414
      @connorpaulsen4414 8 лет назад +5

      Ex: 5*3-6/3*7.
      15-6/3*7
      15-2*7
      15-14
      1

    • @connorpaulsen4414
      @connorpaulsen4414 8 лет назад +39

      The way I learned it was (P-Parenthesis)(E-Exponents)(MD/DM-Multiplication & Division)(AS/SA- Addition & Subtraction)

    • @janwollert1559
      @janwollert1559 8 лет назад +8

      Your lack of faith disturbes me.

    • @absolutenonfactoronthecourt
      @absolutenonfactoronthecourt 8 лет назад +6

      In elementary I did p-e-m-d-a-s but in middle school I'm doing p-e-m/d-a/s

    • @ohmynoun
      @ohmynoun 8 лет назад +42

      Agreed about missing a huge part. This video confused me, because I thought everyone knew that the MD and AS part of PEMDAS meant to complete those in the order they appear. So, on 8-2+1, you'd do subtraction first because it appears first. If anything, this video complicates a very simple operational theory of mathematics.

  • @darksecret965
    @darksecret965 Год назад +2

    The point of the video was that rules like PEMDAS or BODMAS, are not real rules at all. As you study higher mathematics, you will realise there are in fact other number systems with other "rules"
    So how are those things governed? By something called "properties" of that number system. Things like commutativity, associativity, distributability of operations (in this case binary operations) etc. So it's better to see it like that, when things get ambiguous or hazy with oversimplified rules like PEMDAS or BODMAS.

  • @randomguy263
    @randomguy263 5 лет назад +320

    Well, this was painful to watch.

  • @GenericOverload
    @GenericOverload 11 лет назад +40

    I learned PEMDAS differently...
    My teachers said it in this way:
    P
    E
    MD
    AS
    8 - 2 + 1 (according to my teacher) you do subtraction or addition from left to right at the *same* time. So I would get 6 + 1 which equals 7. Guess my teacher taught us right :).
    To clarify...
    I think you just thought of PEMDAS in the wrong way. Most of the kids I know were taught the way I mentioned above. I have never been told to do addition before subtraction (Same with multiplication and division).

    • @chrisosborne7041
      @chrisosborne7041 11 лет назад +7

      Indeed, I was told addition/subtraction and multiplication/division were left to right, therefore always yielding the same answer.

    • @courtn3y345
      @courtn3y345 11 лет назад +3

      that is why the little rhyme thing goes:
      please
      excuse
      my dear
      aunt sally
      the 'my dear' and 'aunt sally' are together because when you are doing +/- you are doing it from left to right, whichever comes first. same with multiplication and division.

    • @vjollcaspahiu6709
      @vjollcaspahiu6709 11 лет назад +2

      OMG! Minutephysics, PEMDAS is set up as gen. overload explained. when doing multiplication and division, you do them from left to right, the same with addition and subtraction. I know I basically just said what gen. overload said, but you get the point. Next time, think a tad before you post influential videos. This generation's children is still learning you know.

    • @shizazzz
      @shizazzz 11 лет назад +1

      I agree here. You (the author of the video) have overlooked a very important part of PEDMAS/PEMDSA

    • @dubbl3rainbows658
      @dubbl3rainbows658 11 лет назад +1

      well my teachers were wrong... they told me PEMDAS not P E MD AS lol i actually learned something from youtube !!! told u mom lol

  • @pinkyfull
    @pinkyfull 8 лет назад +605

    The way i was always taught the subtraction addition and divide multiply were simultaneous. As in there was no preference for one before the other and you just do it in the order they appear in the calculation but i may be odd in that.
    Still love the video though

    • @quantumwillow2734
      @quantumwillow2734 8 лет назад +3

      Me too.

    • @gray546
      @gray546 8 лет назад +25

      exactly. that's how it's taught across the country to my knowledge. I don't think they knew that...

    • @johnjohnson7425
      @johnjohnson7425 8 лет назад +4

      I was also taught this

    • @cmdrblahdee
      @cmdrblahdee 8 лет назад +2

      I'm in the US and that's what I was taught here. I also wasn't taught any kind of acronym, which I suspect is what led to such a misconception. You can't say 'parenthesis before exponents because P is to the left of E', and then go on to say 'the M and D are simultaneous'.
      Strangely though, this did remind me of a calculus problem with an infinite number of 1-1-1's. For some reason, the way to solve the problem was to insert your own parenthesis at various points. Now thinking about the order of operations, this strikes me as a flawed argument.

    • @cat-zp1rg
      @cat-zp1rg 8 лет назад +13

      pinkyfull yeah multiplication and division are grouped together and performed left to right. As well as addition and subtraction

  • @Arthur_da_dog
    @Arthur_da_dog 4 года назад +4

    Problem #1 doesnt give 2 numbers. PEDMAS states that operations must go towards the right. So in 8 - 2 + 1, you always start with the first 2 numbers on the left (8-2) followed by + 1.
    Problem #2 was unclear because of the way it was formulated. When doing a division you should always be using parentheses to clarify what goes with what. Nevertheless, because parentheses arent there you have to use the left-to-right technique. The first 2 numbers, divided by the last number.
    PEDMAS is an acronym to remind young students which set of operations go first. What I mean here is division don't go before multiplication and additions don't go before subtractions. In PEDMAS you start with parentheses, then proceed with exponents, then come division or multiplication (whichever is the left most operation in your equation) and then comes additions or subtractions (again, whichever is the left most operation in your equation).
    You created a non-existent problem to make a video. Normally this wouldn't be an issue seeing as that's almost the definition of youtube now but this is a sensitive for a field where young students can be very uncertain about how they are supposed to do things. PEDMAS is a simple and easy to understand law of mathematic operations that must not be messed with.

  • @lordnate2000
    @lordnate2000 10 лет назад +18

    The big problem with algebra in school, is that you don't know what you are calculating. If you were doing algebra in physics, you would first have to get the data to input into the equation, which means you know what each number represents. This is why story problems are good in school, but they are often under used as random equations are simpler to make and quicker to teach. Still, I've never had difficulty with the order of operations.

    • @thaias9654
      @thaias9654 2 года назад

      ah yes, John with his 200 watermelons, trying to act like that would be a normal scenario anyone would encounter in real life

  • @spaceye
    @spaceye 9 лет назад +79

    Well firstly, as pretty much everyone else has mentioned, we were all taught that multiplication and division should be considered together, not one first and then the second. Same with addition and subtraction. They have the same priority.Parenthesis, then exponents, then multiplication _and_ division, and finally addition _and_ subtraction.
    Secondly, the example example at 0:19 was infuriating. If you use PEMDAS as it was taught, the answer is unambiguously 7. Saying that someone might erroneously solve "8 - 2 + 1" using "8 - 3 = 5" makes no sense. Even if you ignored PEMDAS and looked at the second and third terms first, the result would be -1, which you would then add to 8. Where on earth did you get -3? You can put the terms (8, -2, and 1) in any order and get the same result. This video makes no sense.

    • @aeroscience9834
      @aeroscience9834 9 лет назад +4

      If you follow pemdas literally, then addition comes before subtraction, so " "8-2+1" doing the addition first gives "8-3" or "5". If the rule is to do addition before subtraction then there is implied parenthesis at "8-(2+1)".

    • @marcushaffcon9060
      @marcushaffcon9060 9 лет назад +5

      +Aeroscience Sorry but I was taught the Addition and subtraction are same priority left to right.

    • @DrHotep
      @DrHotep 9 лет назад +1

      +Marcus Haffcon me too. It was definetly 7 to me.

    • @zachogilman7397
      @zachogilman7397 9 лет назад

      spaceye Henry is just saying that people are obligated to do the addition first. I mean
      PEMDAS
      D U
      D B
      I T
      T R
      I A
      O C
      N T
      I
      O
      N

    • @zachogilman7397
      @zachogilman7397 9 лет назад

      Zacho Gilman Stupid Device! I meant to but Addition under the A and Subtraction under the S. But our order of operations has it like this.

  • @LulledLion
    @LulledLion 5 лет назад +36

    Or use Polish notation or RPN, and never worry about order ever again.

  • @Coolguy-ol6pt
    @Coolguy-ol6pt 4 года назад +1

    In Australia it is BIDMAS
    Brackets
    Indices
    Division
    Multiplication
    Addition
    Subtraction
    However we are always taught that multiplication and division are equal and addition and subtraction are equal so you go from left to right

  • @cornekeetels5293
    @cornekeetels5293 8 лет назад +59

    in the netherlands i learned you can swap multiplciation and division, and subtraction and addition. Also we've learned a basic rule is that you always do everything from left to right (except when you have brackets)

    • @toonchagirl
      @toonchagirl 8 лет назад +2

      +Corné Keetels Yeah! Most people do this.

    • @cornekeetels5293
      @cornekeetels5293 8 лет назад +8

      +toonchagirl doesnt that make this video kinda obsolete

    • @cornekeetels5293
      @cornekeetels5293 8 лет назад +5

      +toonchagirl doesnt that make this video kinda obsolete

    • @cornekeetels5293
      @cornekeetels5293 8 лет назад +5

      +toonchagirl doesnt that make this video kinda obsolete

    • @cornekeetels5293
      @cornekeetels5293 8 лет назад +5

      +toonchagirl doesnt that make this video kinda obsolete

  • @whickervision742
    @whickervision742 5 лет назад +151

    I was taught: P, E, M or D, A or S. Not sure how it got misconstrued by other teachers. And depending on how long the division bar was, that determined when you divided.

    • @MrGreensweightHist
      @MrGreensweightHist Год назад

      "And depending on how long the division bar was, that determined when you divided."
      That isn't a thing.

    • @EnderSpy007
      @EnderSpy007 11 месяцев назад +1

      ​@@MrGreensweightHistMaybe they are referring to nested fractions? Like one half divided by one quarter. I'll try and write it out vertically
      1
      --
      2
      --------
      1
      --
      4
      Instead of one divided by (two over one) divided by 4 which would evaluate to one over two over 4. This then either becomes one half divided by 4, or one divided by two fourths. This branch means it could be 1/8 or 2.
      Of course the implication here is that you're supposed to make the lines either shorter or longer depending on which two numbers the fraction is dividing. However this is functionally the same as including parentheses around each component fraction. You could also multiply by the reciprocal and avoid the nested divisions anyway.

    • @MrGreensweightHist
      @MrGreensweightHist 11 месяцев назад

      @@EnderSpy007 yeah, nest fractions are annoying, and that could very well be what they were thinking of, though () would be needed to make that happen in linear
      Using your example....
      1
      ---
      2
      -------
      1
      ---
      4
      Would have to be
      (1/2)/(1/4)
      Otherwise we get left to right priority.
      leading to
      1/8th instead of 2
      I think they missed that aspect.

  • @Biggordon200
    @Biggordon200 6 лет назад +34

    the so called "standard in the u.s" was not how i was taught here in the u.s

    • @noncanot
      @noncanot 4 года назад +1

      order of operation is same across the whole world, math is universal. "standard in the u.s" does not exist. These PEMDAS or PODMAS or any othes stupid acronyme is just acronyme to help kids remember order of operations. It has nothing to do with rules of math. Doesn't matter what acronyme you use, math is still the same.

    • @morgankasper5227
      @morgankasper5227 4 года назад

      @@noncanot Please Excuse My Dear Aunt

    • @SmallSpoonBrigade
      @SmallSpoonBrigade 4 года назад +1

      @@noncanot math isn't quite universal in that sense, but it's pretty close and something like this woud be a pretty big issue.

  • @nutronstar45
    @nutronstar45 2 года назад +4

    there was once a viral equation ( 6/2(1+2) ) which exploits the order of operation, resulting in two possible answers, 6/2*(1+2) and 6/(2*(1+2))
    equations should be as unambiguious as possible, because it is meant to be read by humans
    the equation 6/2(1+2) exploits the ambiguity of implied multiplication, which should be always avoided or properly defined to avoid ambiguity

    • @okaro6595
      @okaro6595 4 месяца назад +2

      Implicit multiplication should not be avoided.

    • @nutronstar45
      @nutronstar45 4 месяца назад

      @@okaro6595 "properly defined"

    • @smartmanapps5588
      @smartmanapps5588 4 месяца назад

      " two possible answers" - no, there's only 1 correct answer, 1. I wrote a whole order of operations thread - textbook references, proofs, the works - which you can find if you search for it (RUclips removes links, except for Wikipedia). In short 2(1+2) and 2x(1+2) aren't the same - the former is 1 Term, the latter is 2 Terms (and so the latter term gets flipped out of the denominator and into the numerator... which is precisely why you should never break up terms).

    • @smartmanapps5588
      @smartmanapps5588 4 месяца назад

      @@okaro6595 There's no such thing as "implicit multiplication" - it's a made-up rule by people who have forgotten about Terms and The Distributive Law (both found in Maths textbooks).

    • @nutronstar45
      @nutronstar45 4 месяца назад

      @@smartmanapps5588 and what do you base your argument on?

  • @GamingKing-jo9py
    @GamingKing-jo9py 5 лет назад +161

    0:52 I learned that addition and subtraction is the same priority
    Edit: definitely =7

    • @SkKedDy
      @SkKedDy 4 года назад

      GamingKing2436 it’s 4

    • @briantorayagiorgana2919
      @briantorayagiorgana2919 4 года назад +2

      @@SkKedDy it's 10^3

    • @leoalper4530
      @leoalper4530 4 года назад +14

      You’re
      The problem: 8-2+1
      8-2=6
      6+1=7
      Done
      If you want to do it the other way (technically you are supposed to go left to right, but addition/subtraction is an exception to this ):
      -2+1=-1
      8-1=7
      Done
      Same answer
      Always go left to right though, safest option

    • @angelmendez-rivera351
      @angelmendez-rivera351 4 года назад +1

      Nuclear Unity Adding negative numbers is not an exception to the left-to-right rule.

    • @Dr.1.
      @Dr.1. 4 года назад

      @@leoalper4530 idk how he ended up with 5 in the vid smh
      it dosent make sens

  • @mrp0001
    @mrp0001 6 лет назад +409

    Wheres mah BODMAS squad at?

    • @pranavsetpal
      @pranavsetpal 5 лет назад +9

      Here

    • @TheMiniMidge
      @TheMiniMidge 5 лет назад +59

      im a BIDMAS boy

    • @HaliPuppeh
      @HaliPuppeh 5 лет назад +32

      BEDMAS here

    • @rkay_bxzq
      @rkay_bxzq 5 лет назад +97

      Ah yes,
      Barentheses
      Ixponents
      Division
      Multiplication
      Addition
      Subtraction

    • @andrewzhang8512
      @andrewzhang8512 5 лет назад +59

      Unknown is actually,
      Brackets
      Indeces
      Division
      Multiplication
      Addition
      Subtraction

  • @micahqgecko
    @micahqgecko 9 лет назад +11

    Um...you do realize that in the United States we are taught that multiplication and division, as well as addition and subtraction, are done on the same step and you do them in order from left to right. If someone in the US said that 8-2+1=5 then they'd be getting 0's on their math tests.

  • @o_enamuel
    @o_enamuel 4 года назад +2

    in Brazil we do in order:
    - What is between parentheses
    - Whatever is exponentiating or rooting, whichever is left first
    - Whatever is multiplying or dividing, whichever is left first
    - Whatever is adding or subtracting, whichever is left first

    • @connorconnor2421
      @connorconnor2421 4 года назад +2

      -radiating?-
      you mean rooting

    • @o_enamuel
      @o_enamuel 4 года назад

      @@connorconnor2421 thaks, I do not speak english very well ...

  • @WanquanInfoPlus
    @WanquanInfoPlus 11 лет назад +10

    It's supposed to progress left to right. You can't just throw in parentheses and say PEMDAS doesn't work. It does work, and because parentheses are done first, you can just put them in and get a different answer, as you did.

  • @TebiByyte
    @TebiByyte 9 лет назад +77

    Okay, clearly there's some confusion in comments. What Henry is saying is this: PEMDAS is right in terms of getting the correct answer, but it's horribly wrong in the fact that it blocks out the beautiful Algebra behind it. As someone who absolutely loves math, I agree with this. If you understand what is actually going on, you'll have no need for PEMDAS, unless of course the expression at hand may have multiple solutions because it doesn't specify, for example 2 - 3 * 3. You could evaluate (1+5)*4 in any way you wanted to, which is the beauty of mathematics. The fact that there are multiple ways to get a right answer is what is beautiful about math, but PEMDAS crushes that, in saying there's only one right way to get it. I believe this is what Henry is trying to say.

    • @demonpenguin9121
      @demonpenguin9121 9 лет назад +4

      12121212131212 I disagree simply because of the fact that neither I, nor anyone I know was ever taught the "left to right" rule. PEMDAS by itself doesn't say anything about left to right.
      Now that being said, you're correct in saying that simply acknowledging this "left to right" rule would solve all the mathematical issues with PEMDAS and give you the correct answer. Though I agree with you as well that the overall point is good. It's better to teach the principles rather than one method that gets you the right answers on your homework.

    • @jumpyed
      @jumpyed 9 лет назад

      Tristan Fullmer Where I live in canada it is taught Bedmas(Brackets instead of Parathesises) and that you complete them in the same order as bedmas, left to right.

    • @barrysmith6935
      @barrysmith6935 9 лет назад +1

      Demon Penguin We were taught it back in the sixties

    • @demonpenguin9121
      @demonpenguin9121 9 лет назад +1

      Barry Smith The more I've talked to other people about this, the more I've found that it really depends on the teacher. Even in the same school the detail about "left to right" isn't always mentioned. Regardless though I still think the overall point is still valid, though the example they used seems to be taken very seriously by other viewers.

    • @ryanm2279
      @ryanm2279 9 лет назад +1

      ***** this is taught to students in the 5th,6th,7th grade, they don't appreciate the beautiful math behind order of operations, they just want to learn the the simple math first, then the great algebra

  • @cacophony7941
    @cacophony7941 6 лет назад +29

    The way I learned PEMDAS was Parenthases, Exponents, Multiplication AND Division (from left to right), then Addition AND subtraction (from left to right). This removes the ambiguity of phrases like 1-1-1-1.

  • @Liggliluff
    @Liggliluff 2 года назад +2

    From the comments, this seems to be focused on what was taught in USA, not the rest of the world. The English speaking world seems to be taught something similar, but different. But people of non-English countries seems to have been taught the correct method.

  • @WindyDelcarlo
    @WindyDelcarlo 10 лет назад +14

    I learned it at
    Brackets (Parenthesis)
    Exponents
    Multiplication and Division (left to right)
    Addition and Subtraction (left to right)
    And it still works through high school. People just need to remember that MD and AS go together

  • @jayjeckel
    @jayjeckel 8 лет назад +175

    That isn't the order of operations I was taught in school in the USA in the 80s and 90s. Mul and Div are of equal rank, Add and Sub are of equal rank, and you left out the left to right rule. The actual order of operations is absolutely correct and if it wasn't, then none of the technology we use everyday would work. Lastly, your "moral" argument at the end is bafflingly silly, order of operations doesn't turn people into robots that can't think for themselves.

    • @jayjeckel
      @jayjeckel 8 лет назад +6

      I mean, I could say the same thing about SquareSpace. It is an immoral mechanical structure that dictates using just one of the many ways of creating websites, locking them into one path through the beautiful html/etc landscape and robbing them of any insight into what they are actually doing when they are creating web pages.... Do you see how silly that sounds?

    • @brittanylaurion6503
      @brittanylaurion6503 8 лет назад +2

      yes he left of the parentheses i learned order of operations with pe(md)(as) which put them on the same level and then we were taught to move left to right

    • @ewhar5227
      @ewhar5227 8 лет назад +2

      yeah, you just multiply and divide left to right

    • @desigirlng
      @desigirlng 8 лет назад +6

      Yeah in Canada we were taught the same thing, but we called it BEDMAS (B for Brackets)

    • @prosincr
      @prosincr 8 лет назад +2

      That's not what it implies. He is saying that you basically just do what a computer does. You don't actually ever get to understand what is going on.

  • @EmeraldMinotaur
    @EmeraldMinotaur 9 лет назад +4

    When I learned this in 5th grade, my teacher made it clear that M does not necessarily precede D, same with A-S

  • @its_rayray9398
    @its_rayray9398 4 года назад +8

    Nobody :
    Minute Physics : aDDiTiOn BEFORE sUbTraCtion

  • @sspence65
    @sspence65 10 лет назад +13

    The standard order of operations in the US does not come up with 5, it comes up with 7. PEMDAS is still correct. Always move from left to right, taking into consideration PEMDAS. & is the only correct ansswer, even with PEMDAS.

    • @ToshimahaIaketa
      @ToshimahaIaketa 10 лет назад +2

      I feel like you are the only one hear who went to school past elementary...

    • @tryithere
      @tryithere 10 лет назад +4

      Toshimahalaketa
      hear????

    • @ToshimahaIaketa
      @ToshimahaIaketa 10 лет назад +2

      sorry.... I have been up god knows how long -_-

    • @Monochromicornicopia
      @Monochromicornicopia 4 года назад

      Because multiplication and division have the SAME priority, that means it doesn't matter what order you take them. Right to left or left to right will give you the same exact answer..

  • @spencermills2147
    @spencermills2147 8 лет назад +40

    Pemdas is correct. Back to the 8-2+1. First, adding subtracting come first, and which ever one is first read from left to right, you do. It's the same way with multiplication and division. Teachers must be teaching pemdas in the incorrect way today I guess. If you do pemdas correctly every time, u get the correct answer.

    • @finnthedog8186
      @finnthedog8186 8 лет назад

      i noticed that too

    • @callanc3925
      @callanc3925 8 лет назад

      You will also get 7 whether you add or subtract first which really makes me doubt minute physics' calculation abilities

    • @Aryasvitkona
      @Aryasvitkona 8 лет назад +1

      +Callan Carne I doubt yours. If you do addition first you get "8-3" which is 5. Please relearn the math I learned in Preschool. I beg you.

    • @callanc3925
      @callanc3925 8 лет назад +1

      (-2+1) is -1 mate. -(2+1) is 3 but there arent brackets in the question indicating to minus the 1

    • @jonathandpg6115
      @jonathandpg6115 8 лет назад

      BEDMAS (the way I learned which is the same) was specified that it's actually BE(DM)(AS) and the dm or the as can be switched depending on the order left to right. it's a quick memory aid to help remember the order

  • @Ravenleaf182
    @Ravenleaf182 5 лет назад +32

    If you are going to correct a "wrong" method, it might be better if you properly understood the method you are trying to correct...This was really poor. you didn't even explain PEMDAS correctly.

  • @CaitSith87
    @CaitSith87 11 месяцев назад +2

    Who on earth does 8- 2 + 1 = 5? I highly doubt that is pedmas. That is just wrong.

  • @XouZ88
    @XouZ88 10 лет назад +83

    I though you would have removed this video by now since it's all wrong. I know you like Physics more than Math but then you post things like this please make sure you are right.
    PEMDAS stands for:
    1. Parentheses
    2. Exponent
    3. Multiplication AND Division _left to right_
    4. Addition AND Subtraction _left to right_
    This is what I learned in school as a kid and if you follow this and you will never get two answers.
    *P.S.*
    BODMAS is the same thing it's just that they have used different words in the beginning.
    B stands for Brackets and O stands for Orders ( which is Exponents and Square Roots etc ) But DM and AS is still _left to right_!

    • @Faneffex
      @Faneffex 10 лет назад +5

      other places in the world dont teach the left to right thing which is why people get it confused, this video is still very informative to the confused group and very helpful, i see no reason to take it down

    • @XouZ88
      @XouZ88 10 лет назад +5

      Benjamin Mourad It would be much easier you just say left to right thing in the video instead of making things more complicated.
      I actually got more confused by this video. If they say that addition should go before subtraction in US something is clearly wrong with the schools there.

    • @Faneffex
      @Faneffex 10 лет назад +2

      the thing is, he said that subtraction is also technically negative addition which is why you go from left to right in cases of no parentheses and a subtraction operator and an addition operator. same for multiplication and division where division is technically less than 1 multiplication

    • @XouZ88
      @XouZ88 10 лет назад +1

      Benjamin Mourad Yes I know that same goes for roots which is exponents less than 1, but he also said that PEMDAS meant Addition before Subtraction in the rules definition which is very wrong. If that's the way USA learn this rule then it is clearly something wrong with the schools in USA as I said before :)

    • @jamalhammoud
      @jamalhammoud 10 лет назад +1

      .

  • @imjustakid724
    @imjustakid724 8 лет назад +13

    Judging by the comments, no one was taught this way.

  • @Johnjkngbaup
    @Johnjkngbaup 10 лет назад +29

    Since when do you always do addition first? You do multiplication/division and addition/subtraction in order from left to right. You don't follow the Mnemonic so concretely. If you actually lived in the US with PEMDAS being taught growing up you would know that.

    • @ThePhantomguy321
      @ThePhantomguy321 10 лет назад +5

      ***** Exactly! You do multiplication/division and addition/subtraction from left to right, not the way it's stated in PEMDAS.
      (I just think he's a little confused).

    • @TheAgnostiic
      @TheAgnostiic 10 лет назад +1

      So it was a flaw on minute physic's behalf to assume such information?

    • @masterkevkev
      @masterkevkev 10 лет назад +8

      Yup.
      Flaw on minute physic's behalf.
      You're right Diddy, it gets me aggravated seeing "Pemdas" called wrong >-> - There's nothing wrong about it!

  • @Eilocke
    @Eilocke 4 года назад +3

    A mnemonic that requires you to have additional information that's not contained in the mnemonic seems like a great way to confuse kids. And once you're an adult, you're not gonna be solving much maths with order of operations. The properties of operations are what really matter, and at a certain point I stopped thinking about order of operations entirely.
    6/3 * 7 * 2 = 6 * 7/3 * 2 = 6 * 7 * 2/3
    Writing equations sensibly helps a lot. If you can help it, use a fraction bar. A slash is also fine, because it's fairly intuitive that it represents a fraction. If you use ÷, and you're not teaching kids, you're basically encouraging people to get it wrong. That seems more like your own fault than theirs. You can do the multiplications in any order, as long as you remember to only multiply by the dividend, not the divisor. As for ambiguity...
    3 / 4x - 2
    BOMDAS (or PEMDAS) doesn't give any precedence to implied multiplication. Even calculators will vary. The solution is to write a less confusing expression. Unless you wanna trick people, in which case you can just write it in wingdings.

  • @connorbredall3112
    @connorbredall3112 4 года назад +87

    0:14 That is not The Order of Operations, or at least that is not how I learned it. I learned PE(MD)(AS) and BPE(MD)(AS). Here is the order that I learned.
    1. Brackets (Exclusive to BPE(MD)(AS).) Later in life I learned this step is unnecessary because brackets can just be substituted for more parenthesis, which would lead to...
    2. Parenthesis
    3. Exponents
    4. Tie between Multiplication and Division.
    5. Tie between Addition and Subtraction.
    6. When in doubt even after following the previous orders, just go left to right.
    That last order abolishes the ambiguity you described between 0:20 and 0:34, meaning that undoubtedly 8-2+1=7 and 6/3/3=2/3. Thus, the premise of this video has been debunked. Also,...
    3:05 - 3:09
    Putting parenthesis there changes the answer.
    1-1-1-1=-2
    (1-1)-(1-1)=0
    Physics has a lot of math in the subject, and this is a physics based RUclips channel. This would be an epic fail even if this channel wasn't a physics based RUclips channel, but since it is it's even more of an epic fail. I mean this channel probably animated this whole thing and probably took a lot of time making it, yet during that entire time you never noticed this. What the fuck?

    • @abigailpena5950
      @abigailpena5950 4 года назад +3

      Wow I learned it just as "parenthesis, exponents, multiplication, division, addition, subtraction" without the "tying" thing... I guess I was one of countless others that were taught wrong...

    • @RummanNaser
      @RummanNaser 4 года назад +2

      "epic fail"
      Bro 2012 is gone
      But yeah I agree, people weren't taught that part. I got to know because of Presh Talwalker

    • @leoalper4530
      @leoalper4530 4 года назад +4

      Abigail Peña
      well what he’s saying is that you don’t do addition before subtraction or vice versa, you simply do the problem from left to right so they are practically tied; they are essentially the same function but in reverse. This one point makes this whole video a waste of time. It’s almost like halfway they realised “oh shoot we fucked up big time” and instead of scrapping the video, they just changed the whole thesis into it being morally wrong rather than mathematically wrong...

    • @youkey1090
      @youkey1090 4 года назад +4

      I know it should be like this
      (1-1)+(-1-1) by dividing the equation into two parts and summing them together
      or (1-1)-(1+1) by taking - as a common factor
      But how care, someone made a mistake on the internet.
      Or maybe it's intentional.

    • @AkashDandere
      @AkashDandere 4 года назад +1

      BRUH

  • @thurmanator7874
    @thurmanator7874 8 лет назад +95

    WTF is Pedmas?
    Here in Australia it is bodmas...

    • @3amwiththebird453
      @3amwiththebird453 8 лет назад +1

      lol yes my fellow aussie

    • @umarahmed1252
      @umarahmed1252 8 лет назад +1

      Bodmas?

    • @butterflyst11
      @butterflyst11 8 лет назад +25

      Bodmas sounds like a holiday where you walk around shirtless.

    • @jodiehock2536
      @jodiehock2536 8 лет назад +6

      same I'm the UK

    • @RobbyBoy167
      @RobbyBoy167 8 лет назад +16

      Americans like being different. They don't want to follow what everyone else does but thinks their stuff is universal.

  • @The__Creeper
    @The__Creeper 11 лет назад +20

    I never learned to do addition before subtraction. When it came to that step, it was always left to right. So it has always been 8+(-2)+1. I've never seen it done any other way.

  • @LeonBlack666
    @LeonBlack666 3 года назад +3

    I was stuck 20 mins in the start of the video screaming and trying to understand how -2+1 is -3...

  • @gavinwarner3480
    @gavinwarner3480 8 лет назад +102

    No because you always go from left to right.

    • @gavinwarner3480
      @gavinwarner3480 8 лет назад +18

      Well that's how I learned it. Addition OR subtraction, whichever is first left to right.

    • @jackmoore4005
      @jackmoore4005 8 лет назад +1

      Bingo

    • @duck6872
      @duck6872 8 лет назад +1

      same

    • @Quintingent
      @Quintingent 8 лет назад +13

      That's a failsafe method. By doing that, you're guaranteed to keep the negative signs attached to the numbers they're assigned to. But it's just that: a *method*. It isn't the underlying system itself.
      It's important because sometimes you can't just go from left to right. For example, here's a basic algebraic expression:
      x - 3y + 2y
      You can't just start from the left, becuse 'x-3y' can't be simplified. Which, by the way, is really what you're doing when you do basic addition: '5+2' simplifies to '7' for example.
      You could say 'just do every possible operation in order', but then you get the wrong answer, because you'll attempt to do '3y+2y', get '5y', and end up with 'x-5y' overall. In reality, the minus sign is attached to the '3y', so the expression can be rendered as:
      x + (-3y) + 2y
      This makes what you need to do more obvious (which is to do '-3y+2y' to get '-y'), but it's still the same expression.

    • @enjoyfanta9382
      @enjoyfanta9382 8 лет назад +1

      David Ward
      Well said. Couldn't have explained it any better than you.

  • @AnhNguyen-ds2hy
    @AnhNguyen-ds2hy 6 лет назад +60

    3:05 shouldn't the answer be -2. I mean if you put it as (1 - 1) - (1 - 1) then obviously the answer is 0. However originally the equation was 1 - 1 - 1 - 1 so if one was to put parentheses in between each number the equation would then become (1 - 1) - (1 + 1) which equals -2.

    • @TheKingWerwer
      @TheKingWerwer 6 лет назад +17

      I had to stop the video and check the comments to make sure i am not retarded, thank you for reassuring me i am not!

    • @LordOfBrownies
      @LordOfBrownies 6 лет назад +4

      I even asked google to evaluate it, while thinking there's something wrong with me.

    • @dman375
      @dman375 6 лет назад +16

      The point of that segment is not to leave equations fup for interpretation... if you really mean (1-1)-(1-1)... then write it that way... use parentheses. But yes, without parenthesis, the correct answer would be -2.

    • @captainpocky
      @captainpocky 6 лет назад +1

      Yeah without parentheses the best way to understand that equation is "positive 1 plus three negative ones" or -2. By arbitrarily adding parentheses to the equation, you could also incorrectly argue that the answer is: 1-(1-1-1) = 1-(-1) = 2

    • @AnhNguyen-ds2hy
      @AnhNguyen-ds2hy 6 лет назад

      Mildura Tech Correct me if I'm wrong but I think he was saying one could put in parentheses and proceed in whatever order they want whenever the answer is ambiguous. I don't think that's how it really works. One could do that but they must also remember to correct the values of whatever operators they're putting into parentheses. Just my opinion.

  • @zacherynicoson9890
    @zacherynicoson9890 7 лет назад +5

    ahem, but Pemdas goes Partenthisis>Exponents>Multiplication OR division (whichever comes first)>Addition OR subtraction (whichever comes first). That's what you learn in school.

  • @___iii3621
    @___iii3621 4 года назад +1

    In my country Philippines, the operations multiplication/division and addition/subtraction are partners... If one of these partners are use in a problem, (Example : 20÷4×5) you go from left to the right. (20÷4=5, then 5×5=25)
    Another example : 10+30-5 = 10+30 = 40 - 5 = 35
    If the problem uses two Divisions or Subtraction Operators, you also go from left to the right.
    Examples :
    9÷3÷3 = 1
    and
    10-4-3 =3

  • @KeithPeters
    @KeithPeters 10 лет назад +38

    PEMDAS doesn't mean addition before subtraction. If someone is teaching that, they're teaching it wrong.

    • @Turtleman404
      @Turtleman404 10 лет назад +1

      P - Parentheses
      E - Exponents
      M - Multiply
      D - Divide
      A - Addition
      S - Subtraction
      Yes it does. If someone is teaching you that it doesn't mean that, they're teaching it wrong.

    • @Bracketmeister
      @Bracketmeister 10 лет назад +4

      Eirik Sæther What they should teach are the four stages of importance. Brackets (or Parentheses) first, Indices (or Exponents) second, Multiplication and Division third, and Addition and Subtraction fourth. Generally, as long as you do * and / before + and -, you'll be okay.

    • @codingmath
      @codingmath 10 лет назад +3

      Eirik Sæther No, no, it doesn't. en.wikipedia.org/wiki/Order_of_operations
      "Mnemonics are often used to help students remember the rules, but the rules taught by the use of acronyms can be misleading."
      "These mnemonics may be misleading when written this way, especially if the user is not aware that multiplication and division are of equal precedence, as are addition and subtraction. Using any of the above rules in the order "addition first, subtraction afterward" would also give the wrong answer to the problem 10 - 3 + 2 "
      If you use the mnemonic robotically, without understanding the actual rules, you're doing it wrong and/or teaching it wrong.
      So PEMDAS is misleading, absolutely. Wrong, not really.

    • @Bracketmeister
      @Bracketmeister 10 лет назад +1

      Coding Math Yes! This is exactly what I'm talking about. Maths is beautiful, more people need to understand it.

    • @DTQueen90
      @DTQueen90 10 лет назад +1

      Exactly! When I was taught this, it was multiplication and division, then addition and subtraction. We only say PEMDAS do help us remember it.

  • @joedaniels7240
    @joedaniels7240 8 лет назад +44

    I learnt it as Bidmas or Bodmas
    Brackets
    indices
    division
    multiplication
    addition
    subtraction

    • @alexgibson-qz5ty
      @alexgibson-qz5ty 7 лет назад +4

      Joe Daniels Same!

    • @natemob1
      @natemob1 7 лет назад +3

      same thing has PEMDAS, just different sayings for Exponents and Parenthesis

    • @adm_ezri
      @adm_ezri 7 лет назад +1

      And a different order, but if America doesn't care about that then it's basically the same

    • @levishhunted7593
      @levishhunted7593 7 лет назад

      Same!

    • @aidanallen1976
      @aidanallen1976 7 лет назад +1

      what's the 'o'?

  • @kyleschultz4939
    @kyleschultz4939 7 лет назад +57

    It's not addition before subtraction or multiplication before division. It's addition OR subtraction / multiplication OR division. It goes from left to right, following the order of operations of course. Here's how it should be written.
    P - Parentheses
    E - Exponents
    M/D - Multiplication or division (whichever comes first from left to right)
    A/S - Addition or subtraction (whichever comes first from left to right)
    Here's an easy way to remember it -
    Please
    Excuse
    My
    Dear
    Aunt
    Sally

    • @chemboy
      @chemboy 7 лет назад

      Kyle Shorts Yeah, we've also been taught frok left to right with Multiplication/Division and Addition/Subtraction. But that didn't stop the other kids from thinking Multiplication first then Division the Addition first then Subtraction

    • @lilyt5268
      @lilyt5268 6 лет назад

      Not if you learnt it as BODMAS

    • @davidrojas9668
      @davidrojas9668 6 лет назад

      What's the O?

    • @fusionpit1429
      @fusionpit1429 6 лет назад

      Please
      Excuse
      MyDear
      AuntSally
      is how I learned it

    • @lilyt5268
      @lilyt5268 6 лет назад

      David Rojas Brackets , operations (squares/powers), division, multiplication, addition, subtraction

  • @mjsteele42
    @mjsteele42 3 года назад +2

    I've been teaching high school math for almost 20 years.
    NEVER have I taught that addition comes before subtraction or multiplication comes before division.
    Unfortunately, rather than listening to their teachers, far too many students just blindly memorize PEMDAS and then they convince themselves that, because M comes before D, multiplication comes before division.
    But that's not what their teacher taught them, I guarantee it.

    • @NeoiconMintNet
      @NeoiconMintNet 3 года назад

      You summed up the issue, the acronym tells you what to do but doesn't actually explain the rules.

    • @CircuitrinosOfficial
      @CircuitrinosOfficial 3 года назад

      Unless you have actually been to every math classroom in the entirety of US history, there is no way for you to actually know with 100% certainty that no teacher has ever taught PEMDAS incorrectly.
      Just because you have not personally seen it happen, doesn't mean it never has.

    • @NeoiconMintNet
      @NeoiconMintNet 3 года назад

      @@CircuitrinosOfficial math is taught with books and they have consistent content, made sure by the education department. So again, when learning you read the book and listen to the teacher so you may get a bad teacher, but if learning by including the book, you would learn the correct rules.

    • @CircuitrinosOfficial
      @CircuitrinosOfficial 3 года назад

      @@NeoiconMintNet Some math classes are only given problem work books. Not text books. Their only information source is the teacher.

    • @NeoiconMintNet
      @NeoiconMintNet 3 года назад

      @@CircuitrinosOfficial the information source is a written book given out by the education department so the teaching is doing it correctly, the book is a reference point and if you know that teachers can be wrong, then you should find out the correct answer elsewhere.

  • @IntelligentReality
    @IntelligentReality 10 лет назад +13

    It doesn't say do addition before subtraction or multiplication before division, it says to do which ever one comes first.

    • @Darticus42
      @Darticus42 10 лет назад +1

      But by simply looking at the acronym, it DOES say that addition and multiplication come first. The acronym needs to be supplied with additional information about interchangeability for it to be correct. Arguing about the concept as a whole, the video is incorrect. Arguing simply about the ambiguity of the acronym, the video is correct.

    • @IntelligentReality
      @IntelligentReality 10 лет назад +5

      Absolutely not. The video is not correct, because they displayed the acronym wrong.
      It supposed to be written as:
      P
      E
      MD
      AS
      In this one, multiplication, division, etc. are on the same level and you must do which ever one comes first.
      The acronym is not ambiguous, he just displayed it wrong.

    • @fsociety6983
      @fsociety6983 10 лет назад +2

      Darticus the Great The entire point of the acronym is to be easy to remember. Adding additional information would make it harder to remember.
      The acronym works because everybody knows that addition is not before subtraction. That's something people are told when they're taught the order of operations in the first place.

  • @anicefluffydemon6643
    @anicefluffydemon6643 7 лет назад +75

    I'm sure you have tons of other comments about this but your video just isn't accurate. I've never heard anyone say that their school taught them that Addition comes before subtraction or that multiplication comes before division and my school didn't teach me that way either. Think of PEMDAS as a group of 4 parts: (P),(E),(MD),(AS). For the last two parts, the two operations are equal in terms of which you solve first, you simply solve from left to right. We simply use "PEMDAS" and teach students to solve from left to right with Multiplication/Division and Addition/Subtraction because I think we can all agree that "PEMDAS" is a lot easier to tell kids than "P, E, M and D, A and S."
    Also, I don't really understand how you think that it's "turning people into robots." It simply helps people remember the order in which operations are solved in an equation. If for whatever reason, you want to throw a thousand unnecessary parentheses into the equation then you're free to do so; But "8+2-1" is not any less equivalent to 9 than "((8+2)-1)=(10-1)." Problems don't have to look like a sideways Wi-Fi symbol to be correct.

    • @ryledra6372
      @ryledra6372 6 лет назад +2

      He did point out that multiplication and division were basically the same operation and addition and subtraction were as well...
      I'd point out that using conventional maths 6/3/3 = 6... it can be seen as a 3 tiered fraction written as (6/3)/3 [rewritten as (6*3)/3] or 6/(3/3) [rewritten as 6/1]. Rather than the 2/3 suggested by BIDMAS (or which ever form you most wish to look at) which would really look something like 6/(3*3).

    • @Tfin
      @Tfin 6 лет назад

      If you've never heard it, then hear it now. We only learned it specifically in that order, and then we got stuck with a single math teacher for 7th and 8th grades who spent a year drilling us on long division and multiplication tables, and another on single digit two number addition and subtraction.

    • @rachelrandant5344
      @rachelrandant5344 6 лет назад +3

      Fluffy Xenomorph I have had some people on Facebook tell me they were taught addition before subtraction. I try to explain they were taught incorrectly, but who is going to believe just one random person on Facebook? 😂

    • @courtney-ray
      @courtney-ray 6 лет назад +1

      Rachel Randant i doubt ppl were taught that way by any math teacher. That’s despite the fact that that is probably how they remember it though

    • @mariannmariann2052
      @mariannmariann2052 5 лет назад

      Yes.
      ( ) -> ⁰ ¹ ² ³ ⁴ ⁵ ⁶ ⁷ ⁸ ⁹ -> * / -> + -. Ones with same priority go left to right.

  • @ShadowRevya9
    @ShadowRevya9 10 лет назад +7

    Pretty sure the point of the video wasn't to say the order of operations will give you the wrong answer, just that it doesn't explain how/why you got that answer.
    Difference between just doing math and actually understanding math.

  • @Billy-lj3nl
    @Billy-lj3nl 3 года назад +4

    A lot of people in the comments are saying that as long as you go left to right with operators of the same precedence (multiplication and division or addition and subtraction), you will for sure get the correct answer. This is true, and is also how I was taught in elementary school, but...
    Subtraction is the addition of a negative number and division is the multiplication of the reciprocal of a number, and both addition and multiplication have the commutative property (order doesn't matter). Like the video mentioned, using facts like this means that you don't have to follow PEMDAS exactly in order to get the right answer.
    Example: 3-2+4=5, which is the same as [3+(-2)]+4=5, which is the same as 3+(-2+4)=5. The problem only arises if you evaluate it as 3-(2+4) = -3, which is actually equivalent to 3-2-4=-3 (if you distribute the negative sign), and is in reality the addition of three completely different numbers than in the original expression.
    The same thing applies to multiplication and division. 10/5/2=1, which is the same as (10 * 1/5) * 1/2 = 1, which is the same as 10 * (1/5 * 1/2) = 1. Once again, you only get a different answer if you evaluate it as 10/(5/2) = 4, which is in reality 10 * 2/5, a completely different expression.
    Going left to right with operators on the same level will get you the right answer, but it's not necessary to do it that way.