If n is the number of trials and p is the probability of suc

If n is the number of trials and p is the probability of success in a binomial experiment, to use the normal approximation to the binomial distribution the stataistician checks that

A. n(1-p) > 5

B. npq > 5

C. np > 5 and n(1-p) > 5

D. np > 5

(All signs have an equals line under)

Solution

Normal Approximation to Binomial Distribution      

n*p>5
n*(1-p)>5
Can use approximation

Ans: Option C, np > 5 and n(1-p) > 5