Exhibit 9-4 The Manager of a Grocery Store Has Taken a Random

Multiple Choice

Exhibit 9-4
The manager of a grocery store has taken a random sample of 100 customers. The average length of time it took the customers in the sample to check out was 3.1 minutes with a standard deviation of 0.5 minutes. We want to test to determine whether or not the mean waiting time of all customers is significantly more than 3 minutes.
-Refer to Exhibit 9-4. The test statistic is

A) 1.96
B) 1.64
C) 2.00
D) 0.056