I thought this was hilarious because it looks like it belongs in an elementary school math class, but it takes quite a bit of non-elementary school work.
@@biggiedrakesnake what rigour got to do with it? No one said anything about "more/less rigourous". Don't come being annoying. Especially without the knowledge to be a good annoyer. If you people couldn't figure it out "9, 8 and 4" by guessing, trying some numbers, don't annoy who is able to.
Solved in my head: [y=notebook, x=backpack, z=markers] 1st equation: (y+1)*x=40 so y+1 and x are both factors of 40: options for y are: 39,19,9,7,4,3,1. 3rd equation: y+3z=33 or 3z=33-y so 33-y is divisible by 3. This leaves only two options for y: y=9 (making z=8 to satisfy equation 3 and x=4 to satisfy equation 1), or y=3 (making z=10 to satisfy equation 3 and x=10 to satisfy equation 1). Only the first option satisfies equation 2 so we've determined the values of each variable and can easily solve equation 4. How exciting.
I guessed the value for each of them My intuition is that since this is for kids, the solutions should be integers (because they probably don’t even know fractions yet) It would also be too messy to write fractions or numbers other than whole numbers on this paper Notice that in the first equation, a notebook and three crayons is 33, which is a multiple of 3 ,so a notebook has to be a multiple of 3 Looking back the first equation, one notebook and a notebook times a backpack is forty. Since a notebook is a multiple of three, the pair of solutions for notebook and backpack respectively could be (3,10) or (9,4) because then the first equation would become 10+3x10 or 4+9x4, which could be simplified to (3+1)x10 and 4x(9+1) respectively. You can see that only these two pairs can form two factors of forty after simplification. (Actually, (39,1) is a valid solution for the first equation, but you can challenge yourself by thinking why it is no valid for the other equations) I checked (9,4) as a solution first, and by luck, this is the correct solution. You can figure out why that is the case. (Hint: consider the second equation)
I guess mine wasn't as elegant (as now that I think back on it, it's more of a trial and error answer), but was much easier for me solve. I turned the equations into: 1. B(N+1) = 40 2. P(B+2) = 48 3. N+3P = 33 Then, what can B be where it is a factor of 40, but also adding two is still a factor of 48, of which there are three solutions (2, 4, and 10). I used the solution of B to figure out N in the first equation, plugged in N for the third equation and making sure that when I subtracted N from 33 I had a multiple of three, and using that to give me P, and using the second equation to make sure that P was also a factor of 48. Again, not as elegant, but took me about 2 minutes to do.
Andy, love the channel, keep making us smarter! I hate these problems though, you see them all the time on social media. They don't design them to make people smarter and teach math, it's made to confuse people and get them arguing about the answer for social media engagement. Not including parenthesis makes order of operations confusing for the average person and changing up your symbols to be multiples is often done vaguely. Could you imagine a world where intelligent content was popular? How exciting!
You stand out by not scribbling the equations with a digipen. You will always get my thumb up. Also your presented problems are not trivial. Please, after you finish the video, pause at last screen for viewer to marvel at this.
If z = 34, then y = -69 (as shown in the video) and x = -40/68, and z + yx = 1268/17 (around 74.59) [520/17 (around 30.59) more than the intended solution of 44].
Tried this from deduction along before watching the video and its quite easy... first one is notebook + backpack * notebook and it gives you 40, and out of my head my first plausible answer was 4 + 9 * 4, i don't even know if there are more but if you start thinking about 4 * 10 that's the first one you get So if the backpack is 4, the only possible answer for the second equation is that the marker is 8, and of course the notebook is 9 so you don't have to do the rest of equations
I asked myself, which number added to a multiplication equals to 40? Considering one of the numbers in the multiplication is the one we sum, it's quite easy, so, if its 1 the multiplication should be 39, it can't be 39, if it's 2 the multiplication should be 38, it cant be 38 or 37, but it can be 36, 9x4=36+4=40 You can solve this equation with very simple logic Back to school logic
Could also have been 5+7x5 or 8+4×8 which would verify the first equation but still be false for the rest of the problem, you stopped at 4 while it was the good solution your logic had more than one possible answer, you just happened to end up on the right one first. (But as kids that s usually how it was done, chucking numbers until you find the solution)
@@emmanueledouard2191 yeah, its interesting that even if the intuitive logic gets you one fitting result, its not necessarily the only correct solution. Which is why relying solely on intuition and "simple logic" is not advised for math problems...
I didn't know that the two markers is 2*the picture of one marker so I just called them different variables and I somehow ended up with 2670554 / 6297 for marker + notebook times backpack. did anyone else do it that way? im kind of curious what the correct answer is if it's done that way
Hey not sure if you see this but I seem to have gotten to different answers. for the yx+x = 40 I took out the x and made it into x(y+1) = 40 which ended up as y=40x-1. Then for the 2nd equation 2z+zx=48 and once again took out the z to get z(2+x)=48 and ended up with x=48/z-2. After I put in the y=40x-1 back into the first equation I got x=+/-1 and worked from there. Is my method not correct?
I don't know man, double recorders is not a good symbol. I wouldn't think people would intuitively know that double recorders is the product of 2 single recorders. I would think that double recorders is its own symbol with its own value.
Great video learned so much from it, but can someone explain that last part for solving for Z I didn't quite understand it 😅(time stamp: 2:40), Thanks🙂
have you taken an algebra class? you should learn it if you do. this type of equation is called a quadratic equation, and it can be solved by factoring. you should look up a tutorial if you don’t know it
Trying to figure it out algebraically might be accurate but time consuming. It is a lot easier to deduce through a little trial and error one equation and the rest quickly follow. I think this is why it is better suited for children. They won't over think it.
I haven't look down all the comments, i offer this as an approach. The numbes must be a bit more than 10 on average. There must be at least a factor of 2^7 ( all four are even, two have factors or 4, one has a factor of 80), if there are more than 7, then one of the numbers must be divisible by 16, and thus 16 would in the sequence this is not the case, so try 8,10,12,14.
It’s not even solvable. 2marker + marker x backpack could be interpreted as either 2m+(bm) or 3m*b All of them are up to interpretation on which way is correct because there’s no parenthesis so there’s a total of 8 possible answers to this 💀 now I get that all the answers are gonna be whole numbers but really. Who the hell devised such a devious plot.
@@What-thaW Not sure when/where you went to school, but PEMDAS is the standard at all the way through university level in the US. No one would say a simple arithmetic expression like that is ambiguous without parentheses
@@fosterslover well I’m not gonna dox myself but I’m going to a pretty good college and the math class I took this summer was adamant about parenthesis. Pemdas really fell out of common usage after middle school for me so. Yeah.
@@What-thaW I don't want you to dox yourself, just wanted to make sure it wasn't a cultural/historical difference of opinion. You could name drop MIT and I wouldn't be impressed, my man/gal. Anyone who knows what's up is going to perform multiplication before addition without parentheses
naw them kids really be solving quadratic equations 💀💀💀💀💀💀
From what I hear Asians are doing them in preschool 😂
@@youresoold1216 no.
no asians come premade with quadratic equation solving skills@@youresoold1216
I was like so confused when I saw the quadratic equations when this is supposed to be an elementary problem 😂😂
@@youresoold1216 Yeah right, even us is not that smart enough to solve that early.
"I don't think we're supposed to have negative numbers here". Yeah that'd be too hard for kids to solve
how about the quadtratic equations? 💀
@@ChessJourney123/r/wooosh
he could prove what value was the true one by throwing them in the third equation to test which one of them would turn 33
No, the reason because there will be no "negative number of notebook", you quoted wrong.
You dont have your negetive amount of pencils
Amateur@@zenedhyr7612
Ah yes disguising Algebra as an elementary exercise a government classic
As a kid I would just chuck in random numbers 😂
And finding the answer faster.
And it would take forever to find 9, 8 and 4.
@@Kikkerv11 not really.
@@samueldeandrade8535yes it would its arguably more rigorous than solving it using quadratics
@@biggiedrakesnake what rigour got to do with it? No one said anything about "more/less rigourous". Don't come being annoying. Especially without the knowledge to be a good annoyer. If you people couldn't figure it out "9, 8 and 4" by guessing, trying some numbers, don't annoy who is able to.
This reminds me of linear programming, and using graphs to solve these types of equations but personally I prefer the algebraic route
Do you mean like the method shown in the video or using some matrix transformations?
@@mateicosti nah its a part of discrete maths
Most easiest asian elementary school maths question
I want more deceptively difficult questions, imagine the chaos that would ensue if you posted what looks like elementary level question on facebook 😂
Solved in my head: [y=notebook, x=backpack, z=markers]
1st equation: (y+1)*x=40 so y+1 and x are both factors of 40: options for y are: 39,19,9,7,4,3,1.
3rd equation: y+3z=33 or 3z=33-y so 33-y is divisible by 3. This leaves only two options for y: y=9 (making z=8 to satisfy equation 3 and x=4 to satisfy equation 1), or y=3 (making z=10 to satisfy equation 3 and x=10 to satisfy equation 1). Only the first option satisfies equation 2 so we've determined the values of each variable and can easily solve equation 4. How exciting.
Cool way to do this
How exciting
"-69" "nice"
if 69 means that, then -69 means none of that 😔
@@RawfunRahmanyes, back to back
@@vincentkingsdale8334 96?
I guessed the value for each of them
My intuition is that since this is for kids, the solutions should be integers (because they probably don’t even know fractions yet)
It would also be too messy to write fractions or numbers other than whole numbers on this paper
Notice that in the first equation, a notebook and three crayons is 33, which is a multiple of 3 ,so a notebook has to be a multiple of 3
Looking back the first equation, one notebook and a notebook times a backpack is forty. Since a notebook is a multiple of three, the pair of solutions for notebook and backpack respectively could be (3,10) or (9,4) because then the first equation would become 10+3x10 or 4+9x4, which could be simplified to (3+1)x10 and 4x(9+1) respectively. You can see that only these two pairs can form two factors of forty after simplification. (Actually, (39,1) is a valid solution for the first equation, but you can challenge yourself by thinking why it is no valid for the other equations)
I checked (9,4) as a solution first, and by luck, this is the correct solution.
You can figure out why that is the case.
(Hint: consider the second equation)
if harvard was elementary school
I guess mine wasn't as elegant (as now that I think back on it, it's more of a trial and error answer), but was much easier for me solve. I turned the equations into:
1. B(N+1) = 40
2. P(B+2) = 48
3. N+3P = 33
Then, what can B be where it is a factor of 40, but also adding two is still a factor of 48, of which there are three solutions (2, 4, and 10). I used the solution of B to figure out N in the first equation, plugged in N for the third equation and making sure that when I subtracted N from 33 I had a multiple of three, and using that to give me P, and using the second equation to make sure that P was also a factor of 48. Again, not as elegant, but took me about 2 minutes to do.
How do even elementary students solve this? They just manually guess each possible number?
theyre just making it look like it the question is handed out not to kids
It's not given to the kids. It's a fun math problem in the last page of the book. It comes with the book
Andy, love the channel, keep making us smarter! I hate these problems though, you see them all the time on social media. They don't design them to make people smarter and teach math, it's made to confuse people and get them arguing about the answer for social media engagement. Not including parenthesis makes order of operations confusing for the average person and changing up your symbols to be multiples is often done vaguely. Could you imagine a world where intelligent content was popular? How exciting!
I hope Andy Math is having fun with these. I sure am. Thanks.
Incredibly exciting
of course he made the length of the video that number
The way i did it was i found a solution that worked for the top one, x + xy =40, and then just solved for one variable at a time.
-69 for some reason got me rolling on the ground lol
Is -69 an unpleasant 69?
@@Sergote12 yes 🥺🥺
This is elementary school in Aisa
Ah yes. Aisa. My favorite place :)
I guess English is not the strongest suit in Asia
You stand out by not scribbling the equations with a digipen. You will always get my thumb up.
Also your presented problems are not trivial.
Please, after you finish the video, pause at last screen for viewer to marvel at this.
My guy what are you yapping on about😂
@@tejassharma5580 nerd
They got kids doing systems of equations? Naaaah
If z = 34, then y = -69 (as shown in the video) and x = -40/68, and z + yx = 1268/17 (around 74.59) [520/17 (around 30.59) more than the intended solution of 44].
it was probably meant to be solved by the trial and error method.
how exciting
You made the video exactly 4:20 long.
Niccccccce😈
Tried this from deduction along before watching the video and its quite easy... first one is notebook + backpack * notebook and it gives you 40, and out of my head my first plausible answer was 4 + 9 * 4, i don't even know if there are more but if you start thinking about 4 * 10 that's the first one you get
So if the backpack is 4, the only possible answer for the second equation is that the marker is 8, and of course the notebook is 9 so you don't have to do the rest of equations
Tf i learn 3 variables system of equation when i was 15. How does these kids get questions like these
if my kid brought this home, i'd totally put in z=34, y=-69, x=-10/17, z+y*x=1268/17 just to mess with the teacher who gave this crap as homework
Is the duration of the video purposely 4:20.😆
LETS. PLUG. IT. IN!
log😅=💧log😄
I asked myself, which number added to a multiplication equals to 40? Considering one of the numbers in the multiplication is the one we sum, it's quite easy, so, if its 1 the multiplication should be 39, it can't be 39, if it's 2 the multiplication should be 38, it cant be 38 or 37, but it can be 36, 9x4=36+4=40
You can solve this equation with very simple logic
Back to school logic
Could also have been 5+7x5 or 8+4×8 which would verify the first equation but still be false for the rest of the problem, you stopped at 4 while it was the good solution your logic had more than one possible answer, you just happened to end up on the right one first. (But as kids that s usually how it was done, chucking numbers until you find the solution)
forgot 10+3x10 too but you understood what my point was anyway
@@emmanueledouard2191 yeah, its interesting that even if the intuitive logic gets you one fitting result, its not necessarily the only correct solution.
Which is why relying solely on intuition and "simple logic" is not advised for math problems...
3:30 top 10 Andy Math moments
how concerning😭
average asian school pop quiz be like:
Nice.
I figured this out in my head after 30 seconds. What’s so hard about it?
good for you
-69/4:20 ... This guy parties
Is it bad that I somehow brute forced my way through it lmao
great video Andy!
I didn't know that the two markers is 2*the picture of one marker so I just called them different variables and I somehow ended up with 2670554 / 6297 for marker + notebook times backpack. did anyone else do it that way? im kind of curious what the correct answer is if it's done that way
Negative 69. Nice!
I'm a child
2:19 is wrong 212z - 40z is not equal to 252z
Hey not sure if you see this but I seem to have gotten to different answers. for the yx+x = 40 I took out the x and made it into x(y+1) = 40 which ended up as y=40x-1. Then for the 2nd equation 2z+zx=48 and once again took out the z to get z(2+x)=48 and ended up with x=48/z-2. After I put in the y=40x-1 back into the first equation I got x=+/-1 and worked from there. Is my method not correct?
y is y=(40/x)-1
x(y+1) = 40. (y+1) =40/x. y = 40/x + 1. Tiny mistake for multiplying 40.
Lil nga take biology
@@XentriaNovanga?
I don't know man, double recorders is not a good symbol. I wouldn't think people would intuitively know that double recorders is the product of 2 single recorders. I would think that double recorders is its own symbol with its own value.
no one mentioning the video is 4:20 min long, and -69 (nice) was a solution
Great video learned so much from it, but can someone explain that last part for solving for Z I didn't quite understand it 😅(time stamp: 2:40), Thanks🙂
have you taken an algebra class? you should learn it if you do. this type of equation is called a quadratic equation, and it can be solved by factoring. you should look up a tutorial if you don’t know it
@@lux5164 My school haven't teached me that so good even though I'm in 9th grade, Idk. But thanks I will go look at it🙂
its called factorization.
Just use the quadratic formula.
A terrible problem for elementary school kids
How you know that two markers are double of one marker?
It's a constant
Bro it's 4:20 minutes long as well lol
No wonder parents hate their elementary schools. jk
-69? Niiiice
Fun fact: this video is 4:20 long
i found 10, 3 and 4 but i think theres like a bunch of solutions, cause i also found 4/3, 29 and 14,4 so yeah
Trying to figure it out algebraically might be accurate but time consuming. It is a lot easier to deduce through a little trial and error one equation and the rest quickly follow. I think this is why it is better suited for children. They won't over think it.
How fucking exciting
real
I haven't look down all the comments, i offer this as an approach. The numbes must be a bit more than 10 on average. There must be at least a factor of 2^7 ( all four are even, two have factors or 4, one has a factor of 80), if there are more than 7, then one of the numbers must be divisible by 16, and thus 16 would in the sequence this is not the case, so try 8,10,12,14.
Tf is happening here
69 NICE
Just teach 7 yr old to use matrix 😮💨
what do goodest mean
-im dumb
Z
It’s not even solvable. 2marker + marker x backpack could be interpreted as either 2m+(bm) or 3m*b
All of them are up to interpretation on which way is correct because there’s no parenthesis so there’s a total of 8 possible answers to this 💀 now I get that all the answers are gonna be whole numbers but really. Who the hell devised such a devious plot.
PEMDAS my dude. It's not ambiguous with standard order of operations
@@fosterslover pemdas is a convention and not the objectively correct way. Although, in elementary school PEMDAS would be treated as such.
@@What-thaW Not sure when/where you went to school, but PEMDAS is the standard at all the way through university level in the US. No one would say a simple arithmetic expression like that is ambiguous without parentheses
@@fosterslover well I’m not gonna dox myself but I’m going to a pretty good college and the math class I took this summer was adamant about parenthesis. Pemdas really fell out of common usage after middle school for me so. Yeah.
@@What-thaW I don't want you to dox yourself, just wanted to make sure it wasn't a cultural/historical difference of opinion. You could name drop MIT and I wouldn't be impressed, my man/gal. Anyone who knows what's up is going to perform multiplication before addition without parentheses