# Binomial Distribution 1

Introduction to the binomial distribution

More free lessons at: http://www.khanacademy.org/video?v=O12yTz_8EOw

**Video Rating: / 5**

More free lessons at: http://www.khanacademy.org/video?v=O12yTz_8EOw

**Video Rating: / 5**

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Sal, that was confusing ?

How will the probability of getting 2 heads be the same as getting 2 tails and also same as getting 3 heads out of all five trials??? EXTREME CONFUSION SAL.

For the probability that two heads are flipped, why are there 5 possible places for the first head? If it's in the fifth position then there is no more room for a second head flip.

thank you for confusing me even more

Thank you very much!

I believe at 9:33 there is an errata: Sal has mentioned

P(X=3)= 5!/(3!3!)

However: it should be: P(X=3)= 5!/(3!2!)

I think sal, in the 3 heads case it should read as

P(X=3)= 5!/(3!2!)

because you solved it like above but written it as

P(X=3)= 5!/(3!3!)

you bother taking the time to say completely irrelevant things; keep it short and straight to the point, we don't need you babbling and trying to be funny, we are just trying to understand this in the simplest and fastest way

He sounds like that crippled guy from family guy

guys the video is too much simple because it explains probability for high-school level or bachelor degree level..he is giving the basics with very simple notations..if you are a grad studies math student "like me" its better to follow MIT grad videos for complex problem solving..however these videos could help to refresh the basic old intuitions ..thank you khan for your great effort..