10C8(3/5)^7(2/5)^2

Question

IT the probability of a basketball player making a given free throw is 3 out of 5, fin the probability that the player makes exactly 7 out of her next 10 free throws using the given.

Answer 1

You are almost right  

 

This is a binomial distribution B(n,p) with parameters n = 10 and p = 3/5.  The probability of getting exactly k successes out of n trials is given by 

 

P(X=k) = _nC_k * p^k * (1-p)^(n-k)  so 

 

P(X=7) = ₁₀C₇ * (3/5)⁷ * (2/5)³