Posted: February 16th, 2017

S there enough evidence to reject the claim at alpha = 0.10? Notice that the sample size is < 30. That will determine whether you use the t-test or the z-test

The IRS claims that the mean wait time for callers during a recent tax filing season was at most 7 minutes. A random sample of 11 callers has a mean wait time of 8.7 minutes and a standard deviation of 2.7 minutes. IS there enough evidence to reject the claim at alpha = 0.10? Notice that the sample size is < 30. That will determine whether you use the t-test or the z-test. See p. 377. Show your hand calculations OR explain how you used Excel to solve.