Chapter 5.2, Problem 2TY

What is the probability that the shopper in Example 2 will be in the supermarket between 31 and 58 minutes? When 200 shoppers enter the store, how many shoppers would you expect to be in the store between 31 and 58 minutes?

EXAMPLE 2

Finding Probabilities for Normal Distributions

A survey indicates that for each trip to a supermarket, a shopper spends an average of 43 minutes with a standard deviation of 12 minutes in the store. The lengths of time spent in the store are normally distributed and are represented by the variable r. A shopper enters the store, (a) Find the probability that the shopper will be in the store for each interval of time listed below, (b) When 200 shoppers enter the store, how many shoppers would you expect to be in the store for each interval of time listed below? (Adapted from Time Use Institute)

1. 1. Between 22 and 52 minutes
2. 2. More than 37 minutes