Blood type AB is found in only 3 of the populationSolutiona

Blood type AB is found in only 3% of the population

Solution

(a) For this question we can use the normal approximation to the binomial distribution because

np = (230)(.03) = 6.9 > 5 and nq = (230)(.97) = 223.1 > 5

We approximate the binomial distribution with the normal random variable with