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 4.1 minutes. The population standard...

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 4.1 minutes. The population standard deviation is known to be 0.6 minute. We want to test to determine whether or not the mean waiting time of all customers is significantly more than 4 minutes.


At a 0.05 level of significance, it can be concluded that the mean of the population is _____.

2) Consider the following.

	Sample A	Sample B
s 2	30	32
n	25	20

We want to test the hypothesis that the population variances are equal.

The test statistic for this problem equals _____.