Question

If X has a binomial distribution, B(n, p) with parameters n and p such that P(X = 2) = P(X = 3), then E(X), the mean of variable X, is 

(A) 2 − p 

(B) 3 − p 

(C) p/2 

(D) p/3

Answer 1

Answer is (B) 3 − p