Question

The mean and standard deviation of a binomial variate X are respectively 6 and 2. Find 

(i) the probability mass function 

(ii) P(X = 3) 

(iii) P(X ≥ 2)

Answer 1

Given, Mean = np = 6 ...(1)

Standard deviation 

(i) Probability mass function

(ii) P(X = 3)

(iii) P(X ≥ 2)