Question: Shopping Time: Housewares

How much customers buy is a direct result of how much time they spend in a store. The mean shopping time for a woman accompanied by children in national houseware stores is 7.3 minutes (Source: Why We Buy: The Science of Shopping by P. Underhill). A retail research team is studying shopping habits in the Cherry Creek Mall (Denver). A random sample of women shoppers with children in a large houseware store gave the following shopping times ( in minutes):

7.7 8.1 8.2 9.0 5.8 9.3 8.4 6.9 12.1 9.4

8.1 6.2 7.3 7.9 8.2 8.5 7.2 6.3 9.1 8.8

a.) Use a calculator with mean and standard deviation keys to verify that \[\bar{X}\] ≈ 8.1 min and s ≈ 1.4 min.

b.) Assume shopping time follows an approximately normal distribution. Use a 5% level of significance to test the claim that the average shopping time for women with children in the Cherry Creek Mall is higher than the national average for this type of store.