Solve the problem.
-The probability is 0.7 that a person shopping at a certain store will spend less than $20. For groups of size 24, find the mean number who spend less than $20.
A) 7.2
B) 16.8
C) 6.0
D) 14.0

Question

Quizplus · Accepted Answer

The probability of someone spending less than $20 is 0.7. Therefore, the probability of someone spending more than $20 is 0.3.

For a group of size 24, we can use the binomial distribution to find the mean number who spend less than $20:

μ = np = 24 x 0.7 = 16.8

Therefore, the mean number of people who spend less than $20 in a group of 24 is 16.8, which corresponds to choice B.

Solve the Problem. -The Probability Is 0.7 That a Person Shopping at a Shopping