#14

Ice Cream: Flavors

What is your favorite ice cream flavor? For people who buy ice

cream, the all-time is still vanilla. About 25% of ice cream sales are vanilla. Chocolate accounts

for only 9% of ice cream sales. Suppose that 175 customers go to a grocery store today to buy

ice cream.

(a) What is the probability that 50 or ore will buy vanilla?

(b) What is the probability that 12 or more will buy chocolate?

(c) A customer who buys ice cream is not limited to one container or one flavor. What is the

probability that someone who is buying ice cream will buy chocolate or vanilla? Assume

that the choice to buy one flavor is independent of the choice to buy another flavor. Then

use the multiplication rule for independent events, together with the addition rule for

events that are not mutually exclusive, to compute the requested probability.

(d) What is the probability that 50 to 60 customers will buy chocolate or vanilla ice cream?

Hint

: Use the probability of success computed in part c.