An Introduction to the Binomial Distribution

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  • Опубликовано: 1 окт 2024
  • An introduction to the binomial distribution. I discuss the conditions required for a random variable to have a binomial distribution, discuss the binomial probability mass function and the mean and variance, and look at two examples involving probability calculations.
    The estimated probability of a 90 year old Canadian male surviving for one year was taken from Statistics Canada life tables, which can be found at www.statcan.gc..... The probability given in the table is the estimated probability that a randomly selected Canadian male, given survival to his 90th birthday, survives until his 91st. I simplified this explanation a little in the example in the video.
    For those using R, here is the R code to find the probabilities for the examples in this video:
    Die roll example.
    Finding the probability of getting exactly two fives in three rolls:
    dbinom(2,3,1/6)
    [1] 0.06944444
    Twenty randomly sampled 90-year old Canadian males example.
    Finding the probability that exactly 18 survive for at least a year:
    dbinom(18,20,.82)
    [1] 0.1729609
    Finding the probability that at least 18 survive for at least a year:
    dbinom(18,20,.82)+dbinom(19,20,.82)+dbinom(20,20,.82)
    [1] 0.2747932
    or
    1-pbinom(17,20,.82)
    [1] 0.2747932

Комментарии • 420

  • @tychothorpe4515
    @tychothorpe4515 10 лет назад +402

    where Khan Academy failed you my friend helped loads

    • @jbstatistics
      @jbstatistics  10 лет назад +52

      I'm glad to hear it helped! Cheers.

    • @surujdeka8544
      @surujdeka8544 7 лет назад +1

      Tycho Thorpe me also bro.khan academy 🤕🤕🤕

    • @monalisanokhemane3099
      @monalisanokhemane3099 5 лет назад +7

      @@surujdeka8544 I also just came from a Khan academy to this one

    • @johnhammer8668
      @johnhammer8668 4 года назад

      @@monalisanokhemane3099 So true

    • @archanamaurya89
      @archanamaurya89 4 года назад +6

      @@monalisanokhemane3099 Hahaha, wow! I really thought I was the only one like that. Felt dumb to not understand even Khan academy video because they teach school level stuff, but this video did much much better than KA :)

  • @KetanSingh
    @KetanSingh 5 лет назад +81

    How the heck am I finding this channel only in 2019? This is a gem of a channel!

  • @CrystalDataMusic
    @CrystalDataMusic 9 лет назад +150

    Your videos are very helpful. Also your voice is pleasant.

    • @jbstatistics
      @jbstatistics  9 лет назад +7

      +CrystalData Thanks!

    • @VazkuuBruh
      @VazkuuBruh 8 лет назад +1

      Hi JB,
      I was wondering if you could tell me why count the probability of failure too? For example, most questions ask for the probability of success but for some reason we count the failure too? Why is that?

    • @joshuafann9650
      @joshuafann9650 8 лет назад +2

      Because you are calculating the probability of X=x, or that x is equal to exactly something. By leaving off the probability of failure, then you are essentially saying the third roll doesn't matter, it can be a success or failure. For example, in the die problem, we were looking for exactly two 5s. However, if you calculate just the probability of two successes and leave off the third roll, then you get 0.083. Now, notice that if you calculate the probability of exactly two successes and a failure you get 0.069, and if you calculate the probability of exactly three successes then you get 0.014. Adding these together you get 0.083. Therefore, if we are looking for exactly two successes and one failure, then we need to add the probability of the failure in, which in the case of the die example, gives us 0.069.

    • @bengper8044
      @bengper8044 5 лет назад

      The best is when you watch it on 2x speed

    • @steshanplaci6373
      @steshanplaci6373 4 года назад +1

      Flirting in the classroom *wink* *wink*

  • @EWOKakaDOOM
    @EWOKakaDOOM 8 лет назад +19

    You are a fucking savior.

  • @greenElement
    @greenElement 5 лет назад +39

    Meanwhile my textbook is speaking to me in a foreign language.
    Thank you so much!

  • @patriciapinilla6654
    @patriciapinilla6654 10 лет назад +34

    Extremely well explained, very clear and very logical presentation. It is one of the best educational videos I've seen. Thank you!

  • @djgumz7063
    @djgumz7063 8 лет назад +124

    You just saved my degree thanks

    • @opq3264
      @opq3264 4 года назад

      ill wait till i see my mark to say the same

    • @мВладислав
      @мВладислав 4 года назад

      @@opq3264 and how?

    • @opq3264
      @opq3264 4 года назад +1

      м Владислав My final is next week , but let me tell it’s not looking good at All for me 🤦‍♂️

    • @viktorbranco8362
      @viktorbranco8362 4 года назад +5

      Are you rich now?

    • @мВладислав
      @мВладислав 4 года назад

      @@viktorbranco8362 haha :D

  • @jbstatistics
    @jbstatistics  11 лет назад +62

    Hi. Thanks for the feedback. Most of my videos move at a fairly quick pace, but some are a little bit slower. I take a bit of a different approach than many others, and moving things along at a decent clip is part of that approach. My pace in this particular video is just a smidgen faster than I'm aiming for. I imagine that at some point in the not-too-distant future, we'll have full control over playback speed so it will be easy to adjust that to one's own tastes. Cheers.

    • @janeadita7489
      @janeadita7489 3 года назад +10

      your prediction was right!

    • @amritas2400
      @amritas2400 3 года назад +8

      Prophet

    • @jackshaak
      @jackshaak 2 года назад

      Spot on, sir!
      And many thanks for the great tutorial !

    • @msachinkumar9886
      @msachinkumar9886 2 года назад +2

      genuinely your explanation are bit fast but they are very precise and very good ,thanks for helping so many and ofcourse me.

    • @thomasnielsen5580
      @thomasnielsen5580 Год назад +1

      He saw the future

  •  7 лет назад +20

    Excellent Video :) Truely , you are the best teacher.

  • @justinrobertson6693
    @justinrobertson6693 9 лет назад +41

    I missed 3 lectures due to work and an illness. Thank you very much for making such wonderful videos illustrating these topics.

    • @jbstatistics
      @jbstatistics  9 лет назад +3

      +Justin Robertson You are very welcome Justin. I'm glad you've found them helpful!

  • @mywellbeing985
    @mywellbeing985 9 лет назад +18

    Thanks a lot! You saved my grade!! My professor and textbook are horrible

  • @j.o.s.h.o
    @j.o.s.h.o 2 года назад +11

    These videos are SO good. They should be supplemental material for all intro uni stats courses

    • @jbstatistics
      @jbstatistics  2 года назад +1

      Thanks for the very kind words!

  • @lilredcrayon
    @lilredcrayon 11 лет назад +6

    You're quite articulate, JB. The visualizations really help. It helps that you do several examples from different angles for each problem. Thanks for connecting the dots!

  • @TinyMaths
    @TinyMaths 5 лет назад +6

    This gave so much clarity amidst the confusion I had on this subject. You made it seem so simple. Thank you.

  • @colemckinnon6402
    @colemckinnon6402 6 лет назад +6

    Seriously some of the highest quality math lessons I've come across!

  • @veebee3969
    @veebee3969 4 года назад +1

    I do not have a mathematical background but find your videos are clear and helpful. I struggled with solving the equation. Would you please explain how you arrived at 0.173 from the 1st line? 0.82^18 = 0.0281; (1-0.82)^2 = 0.0324; 0.0281 x 0.0324 = 0.0009. I am missing something.

    • @andersloren8020
      @andersloren8020 2 года назад

      You forgot the (n k): 20!/18! --> (20*19*18!)/(2*1*18!) = (20*19)/(2*1) = 10*19 = 190. Now, 190*0.0281*0.0324=0.173

  • @eleanorfulani
    @eleanorfulani 9 лет назад +4

    Thank you very much this was so helpful 😃✔️✔️

  • @timurakhtemov7177
    @timurakhtemov7177 2 года назад +4

    My professor does not explain this NEARLY as good as you. Everything I learned in class felt like a jumbled mess. You took all of that and made it crystal clear. Thank you so much.

  • @musicmanxii
    @musicmanxii 11 месяцев назад +1

    You guys have one where you pretend to explain this to a five year old? I might need that one.

  • @stefaniac2095
    @stefaniac2095 8 лет назад +4

    amazing teacher, you made my statistics class go by smoothly. Thank you.

  • @BananaBeecher
    @BananaBeecher 6 лет назад +5

    Absolutely smashing video.

  • @wootwootsoup
    @wootwootsoup 4 года назад +2

    This was very helpful, thank you

  • @diencai1812
    @diencai1812 4 года назад +3

    Love your work! Thank you so much for educating me.

    • @ishamathstea9019
      @ishamathstea9019 4 года назад +2

      Hye Dien 💓
      I have just posted how to find probability using Binomial Distribution..... I hope it's helpful....

  • @supernova7870
    @supernova7870 3 года назад +2

    Watching this video in 2020 , still can't believe you deliver this quality content 7 years back .
    Truely Amazing.

    • @sivakumar-vn7ex
      @sivakumar-vn7ex 3 года назад

      6:42 Bro ,can you tell me why he is forming a tree like that? I can't understand the tree structure.

  • @InLoveWithFunkyPanda
    @InLoveWithFunkyPanda 9 лет назад +3

    this is so great. this is the third video I watch in a row because those topics are part of 1 chapter that I have on my Midterm on Saturday. and you're covering them quite nicely !! :)

    • @InLoveWithFunkyPanda
      @InLoveWithFunkyPanda 9 лет назад

      It's like you're doing exactly what my teacher wants me to learn for my exam! haha

  • @johnhammer8668
    @johnhammer8668 4 года назад +1

    Thanks so much . That tree diagram is very helpful.

    • @ishamathstea9019
      @ishamathstea9019 4 года назад

      Hello John💓
      I have just posted how to find probability using Binomial Distribution..... I hope it's helpful....

  • @margaret.c.phiri.
    @margaret.c.phiri. 2 года назад +1

    How do you punch in everything on your calculator sir 😭😭

  • @JohnCena-hu3jq
    @JohnCena-hu3jq 3 года назад +2

    hidden gem of youtube

  • @vitalinaolia4169
    @vitalinaolia4169 7 лет назад +2

    please can anyone explain how he calculated the answer to be 0.173, 0.083, 0.019. please i am getting confused with the calculation. i think the lecturer calculation is wrong compare to my own interpretatin

  • @anavillanua6505
    @anavillanua6505 8 лет назад +2

    I'm from Spain, and I always see your videos when I need help because the way you explain the lesson is awesome and your pronunciation helps me a lot. Thank you so much!!!

    • @jbstatistics
      @jbstatistics  8 лет назад

      +Ana Villanúa You are welcome Ana! I'm very glad to be of help!

  • @jbstatistics
    @jbstatistics  11 лет назад

    You are very welcome Ahmed. I'm glad to hear my video helped!

  • @niajones208
    @niajones208 3 года назад +1

    I was failing A level maths and this helped so so so much, thank you so much

  • @celalozdemir8565
    @celalozdemir8565 2 года назад +1

    im so sad that i found this channel a day before my statistics final

    • @jbstatistics
      @jbstatistics  2 года назад

      Better to find the good stuff a little late than not at all. I hope your final goes well!

  • @陈俊杰-m2b
    @陈俊杰-m2b 4 года назад +1

    thanks for saving me

  • @yeah1010101
    @yeah1010101 9 лет назад +2

    Your videos are the best!!! Seriously, thanks for saving my stats grade!!

    • @jbstatistics
      @jbstatistics  9 лет назад +1

      +canucklehead You're very welcome! Thanks for the compliment!

  • @databloke2755
    @databloke2755 2 года назад

    How to multiply the (20 and 18) to the other equation. Will you be able to show the work as well in your future videos. How you arrived to the number 0.173.

  • @cobblebrick
    @cobblebrick 2 года назад +1

    I'm watching this after a long day at 6 am and it STILL makes sense. That's how good this video is.

  • @radwan7267
    @radwan7267 5 лет назад

    Hello I have a question please what dose the number 0.173 mean in English? Is it 17% of 18 men will stay stay suivre ? Means only 3 men out of 18 men will stay alive for the next year ? Thanks

  • @jayweber3020
    @jayweber3020 4 года назад +6

    Dude is an amazing instructor and secretly funny af. thanks for saving my grade!

    • @ishamathstea9019
      @ishamathstea9019 4 года назад +1

      I have just posted how to find probability using Binomial Distribution..... I hope it's helpful....

  • @soliderarmatang5664
    @soliderarmatang5664 9 лет назад +3

    you deserve more subs, god bless u

  • @likevideolike2999
    @likevideolike2999 3 года назад

    This is very good explanation, but at 5:48 this ans is incorrect. n/x must changed to Nfacorial by Rfactorial - nfacorial-xfactorial.

  • @GoodLuckForever-wi9kb
    @GoodLuckForever-wi9kb 10 месяцев назад

    Well Done
    Thast really Gem droping such knowledge
    Thanks Sir

  • @alireza98325
    @alireza98325 4 года назад +1

    I can't think of a better explanation than yours.

  • @xxxx-fw2kk
    @xxxx-fw2kk 3 года назад +1

    Great video man, really helpful !!

  • @FU-Utube
    @FU-Utube 9 лет назад +43

    I feel like skipping the rest of my 55min lectures, which I don't understand at all, and just watch your videos. It would be much more efficient.
    Thanks again!

  • @adammontgomery7980
    @adammontgomery7980 3 месяца назад

    I love having equations explained to me in a way I understand. Thank you

  • @wwdeuswwhector_3822
    @wwdeuswwhector_3822 3 года назад +1

    9:05

  • @thulanincube4817
    @thulanincube4817 3 года назад

    Your voice sounds like Jarred Dunn, from Silicon Valley!

  • @黎銘-s9n
    @黎銘-s9n 3 года назад

    in R, P[X = x] = dbinom(x, trials, probability).

  • @TakeFlow1
    @TakeFlow1 2 года назад

    well, it seems that youtube is the future of learning
    the quality of these videos is way higher than college lectures

  • @jimmydim2212
    @jimmydim2212 5 лет назад +1

    Subbed, because you are the man.

  • @praisethankgivingworshipsongs
    @praisethankgivingworshipsongs 8 лет назад +2

    Thank you So Much.

  • @IqraRiazRana
    @IqraRiazRana 6 месяцев назад

    i can't like this video enough(usually i dont comment very much but this thing i could not understand and you explained it very well!! may Allah bless you!!!)

    • @jbstatistics
      @jbstatistics  6 месяцев назад

      Happy to be of help! Thanks for the kind wishes :)

  • @simonkibera4722
    @simonkibera4722 3 года назад

    Sir thank you for your quality lessons, in example of, "According to statistics Canada......." where was n=20 derived from?

    • @jbstatistics
      @jbstatistics  3 года назад

      In the problem I stated "If twenty 90-year old Canadian males are randomly selected..."

  • @abcdef2069
    @abcdef2069 9 месяцев назад

    at 1:19 if independent, why is it like pIIx = p ^ x , that is read as (p pi x) this statistics comes from the fact as to when the balls are distinguishable and replacement is possible for trials.
    even when the balls are indistinguishable, but the binomial statistics treats the balls indistinguishable... this is what i MUST know.
    wish to fundamentally derive the binom distribution from (number of outcomes you want) / (total number of trials). what would be the total number of trials here for a starter?

    • @jbstatistics
      @jbstatistics  9 месяцев назад

      I genuinely do not know what you are asking. For example, I could only guess as to the intended meaning of this:
      "even when the balls are indistinguishable, but the binomial statistics treats the balls indistinguishable... this is what i MUST know."
      First, we have to speak the same language. In the binomial there are n trials. That's the number of trials. But that's not what you mean by trials in your last sentence.
      Also, not all probabilities boil down to (# of outcomes that result in the event)/(Total # of outcomes). That's only true when the outcomes are equally likely.

  • @jazzyjazmin18
    @jazzyjazmin18 9 лет назад

    I like your fast version explanations better because they are sassier.

  • @wraster07hp36
    @wraster07hp36 3 года назад

    Love you, thanks dude. You are auxiliary for me.

  • @lisapurnawati884
    @lisapurnawati884 10 лет назад +1

    Bravo! Your explanation is very clear and helpful! Excellent!

    • @jbstatistics
      @jbstatistics  10 лет назад

      Thank you! I'm glad to be of help.

  • @aprtyuipmkmbkbmk443
    @aprtyuipmkmbkbmk443 7 лет назад +4

    Legendary video

  • @murtuzahamayun9544
    @murtuzahamayun9544 2 года назад +1

    Watching these videos in 2022 🤟🏽

    • @jbstatistics
      @jbstatistics  2 года назад +1

      They're still the best :)

    • @murtuzahamayun9544
      @murtuzahamayun9544 2 года назад

      @@jbstatistics it really helps me, hopefully my test will be fine tomorrow

  • @gogaqazi
    @gogaqazi 10 лет назад +1

    Sir!!! I salute you!!! Thanks a lot for your lectures. I am enjoying your lectures. i was so scared of probability. THANKS A LOT SIR!!! GOD BLESS YOU. i was almost at the verge to drop this class, and your lectures has just showed me some hope.

    • @jbstatistics
      @jbstatistics  10 лет назад

      You are very welcome Usman! I'm very glad you've found my videos helpful. All the best.

  • @Higgsinophysics
    @Higgsinophysics 4 года назад

    Sorted out all my problems - thank you

  • @aryanshah3354
    @aryanshah3354 4 месяца назад

    this explanation was so good!! thank you so so much

  • @tracyholtz6525
    @tracyholtz6525 10 лет назад +1

    Once again thank you. My instructor teaches in the same manner that you do and with these videos to reinforce everything it gives me the supplemental instruction I need. I am going to subscribe to this channel and use these videos to help study for my tests.

    • @jbstatistics
      @jbstatistics  10 лет назад +1

      You are very welcome Tracy. I hope you find my videos very helpful!

  • @freakphysics
    @freakphysics 4 года назад +1

    Man, seriously, as an educator myself I can tell
    you are outstandingly good at this.

    • @vonfiller5166
      @vonfiller5166 4 года назад

      i need help i dont get howhe got 0.173 at 11 mins

  • @pratiksapkota5083
    @pratiksapkota5083 2 года назад

    sorry how is it 0.173? i keep getting 0.001???

  • @KirillBezzubkine
    @KirillBezzubkine 2 года назад

    6:05 - that was the key revelation to me about the formula!!!

  • @gouthamsandyreddy
    @gouthamsandyreddy 9 лет назад +3

    Thanks a ton. Great help in getting the basic understanding right

    • @jbstatistics
      @jbstatistics  9 лет назад

      gouthamsandeep reddy You are very welcome. I'm glad to be of help!

    • @AnasBinHarharah
      @AnasBinHarharah 9 лет назад +1

      jbstatistics A great help. Love your clear accent and understandable examples. Thanks a lot. im sharing it with my course mates.

    • @jbstatistics
      @jbstatistics  9 лет назад +1

      Anas Bin Harharah You are very welcome!

  • @wasifrana7608
    @wasifrana7608 10 лет назад

    Suppose Y follows a binomial distribution with n=2 and p=1/2. Find F(y)

  • @Commander_In_Cheese
    @Commander_In_Cheese 3 года назад +1

    Sensational stuff

  • @sweetpeek4063
    @sweetpeek4063 7 лет назад

    I try to calculate the toss coin and the CANADIAN ...
    the toss coins equals to "0.0833 and not 0.0694" X.x WHY???
    AND FOR CANADIAN
    "its 20.6809 not 0.173" WHY?? I TRY CALCULATING IT 3TIMES BUT ITS THE SAME ANSWER ??? O.O???

    • @sweetpeek4063
      @sweetpeek4063 7 лет назад

      FEED BACK PLEASE ~< T.T

    • @jbstatistics
      @jbstatistics  7 лет назад

      I don't know where your numbers are coming from. (It's not obvious to me what your calculation error is.)

  • @joelcummings
    @joelcummings 10 лет назад

    I think the 90 year old men who want to live another year would be very worried about that serial killer however.
    Great video though, helped out a lot.

    • @jbstatistics
      @jbstatistics  10 лет назад

      I'm glad you found the video helpful! (I wasn't saying that we don't care about 90 year old men dying, just that the serial killer scenario was a little far fetched and probably something we needn't worry about :)

  • @ganapatibiswas5858
    @ganapatibiswas5858 Год назад

    I wish I learned probability in this way earlier.

  • @DilkiAyesha-h6u
    @DilkiAyesha-h6u 2 месяца назад

    This is sooo helpful. Thank you so much!

  • @davidchong2500
    @davidchong2500 4 года назад +1

    Thank you

    • @ishamathstea9019
      @ishamathstea9019 4 года назад

      Hye David Chong💓
      I have just posted how to find probability using Binomial Distribution..... I hope it's helpful....

  • @hopewald3476
    @hopewald3476 10 месяцев назад

    Do you need to use your calculator to solve (n choose x)

  • @vitalinaolia4169
    @vitalinaolia4169 7 лет назад

    please how did he finalize the result to be 0.173.pls can anyone simplify the calculation for me please.Read the question from according to statistics canada life tables. i would be highly anticipating for the kind and loving person

  • @vonfiller5166
    @vonfiller5166 4 года назад

    I'm getting 9.1x10^-4 ???

  • @jaganmohan5518
    @jaganmohan5518 7 лет назад

    well...video is fantastic, but only thing i didnt get is in Canadian problem...the probability of any 90 year ppl is 0.82,so if we select exactly 18 out of 20 the probablility is 0.173,i suppose it shuld be much higher than tat

    • @jbstatistics
      @jbstatistics  7 лет назад +1

      Thanks for the compliment! The probability that exactly 18 out of 20 survive for at least a year is indeed 0.173. If this doesn't feel correct to you, consider the fact that there are many other counts that are quite likely as well, e.g. P(X=15) = 0.149, P(X=16) = 0.213, P(X=17) = 0.228, P(X=19) = 0.083 (as illustrated in the probability histogram).

    • @jaganmohan5518
      @jaganmohan5518 7 лет назад

      oaky...got it

  • @joycewu7703
    @joycewu7703 2 года назад

    Bro, you are saving my life :) Thanks for your uploading in 2013.

  • @scholium3370
    @scholium3370 10 лет назад

    In around 14 minutes you made the binomial distribution crystal clear, whereas my lecturer couldn't do it using 120. My hat stays off around you sir.

  • @preciousjohnkalio9504
    @preciousjohnkalio9504 2 года назад

    This video was very helpful to understand binomial distributions in probability💃

  • @davidyusaku
    @davidyusaku 3 года назад

    Mans out here doin God's work
    Thank you sm for the crystal clear guidance

  • @shadmansakib9151
    @shadmansakib9151 10 лет назад

    i am a student of applied statistics & guess what my probability teacher sucks . thank u JB for making this easy to understand

  • @denlogv
    @denlogv 3 года назад

    Brilliant video, helped me a lot! But I have a question: shouldn't the probability mass be the highest on the value, which is closest to the mean (16 in this case and not 17) or is such an assumption illogical?
    In other words, is there any intuition as to why 17 at 11:20 is more probable than 16?

  • @surujdeka8544
    @surujdeka8544 7 лет назад

    thanks thanks thanks thanks thanks thanks thanks thanks thanks thanks thanks thanks thanks thanks thanks.

  • @shashinidulakshi7318
    @shashinidulakshi7318 4 года назад

    such an amazing explanation.thank you very much ,,,,,

  • @ShadowZZZ
    @ShadowZZZ 4 года назад

    sorry, didnt get anything

  • @yavuzcangz5681
    @yavuzcangz5681 8 лет назад

    so in the table at 11:40 I didnt get that. For explaining further, is it says that 6 men to survive exactly has 0 probability??

  • @sandipburhagohain371
    @sandipburhagohain371 2 года назад

    Thank you and Grateful.

  • @AJ-et3vf
    @AJ-et3vf 2 года назад

    awesome video! thank you!

  • @anuvrattiku3244
    @anuvrattiku3244 4 года назад

    Brilliant ... phenomenal video

  • @jakehealthx
    @jakehealthx 3 года назад

    Wow, this explanation was immensely helpful. Thank you!!

  • @tayyabikhlaq5354
    @tayyabikhlaq5354 4 года назад

    Gold video love your channel plz keep doing that stuff.

  • @Shery0204
    @Shery0204 6 лет назад

    The book didnt make any sense, but you did. Really helpful, thanks!

  • @ahmedaboaldahab453
    @ahmedaboaldahab453 8 лет назад +14

    Now i can go to my exam =D thanks

    • @jbstatistics
      @jbstatistics  8 лет назад +4

      +ahmed aboaldahab You're welcome! Best of luck on your exam.

  • @SyafiqaahIdris
    @SyafiqaahIdris 9 лет назад

    Thankyou so much.. This has helped me a lot as statistics is not my favourite subject. Anyways, great video. Keep it up :)

  • @mahmoud-khaled-abo-elmagd
    @mahmoud-khaled-abo-elmagd 3 года назад

    this a really beautiful video

  • @VirmanaMarketing
    @VirmanaMarketing 4 года назад

    fantastic job! Thank you for putting together the video.

  • @agarciasanz
    @agarciasanz 11 лет назад

    Hi, I found the videos very clear and useful. One small comment: you should slow down a little bit the pace at which you present. The explanation goes too fast and it's easy to get lost when trying to figure out what you say. Best!