Question

X is a binomial variable with parameters (n=5,p=0.25). Find mean and variance of X. Also find P(X<2).

Answer 1

q=1_p

=0.75

mean=np=5×0.25=1.25

variance =npq=1.25×0.75=0.9375

P(x<2)=p(x=0)+p(x=1)

=(.75)^5+5(0.75)^4.(.25)^1