Blood type AB is found in only 3% of the population†. If 240 people are chosen at random, find the probability of the following. (Round your answers to four decimal places.)

Question

(a) 5 or more will have this blood type
(b)between 5 an 10 will have this blood type

Answer 1

Here's one way to do this problem:

n = 240
p = .03
q = 1 - p = 1 - .03 = .97

For (a), you will need to find P(0) through P(4). Add together, then subtract the total from 1 for the probability.

I'll let you try (b).

You can use a binomial probability table or calculate by hand using the following formula:

P(x) = (nCx)(p^x)[q^(n-x)]

I hope this will help get you started.