.The local swim team is considering offering a new semi-private class aimed at entry-level swimmers,but needs a minimum number of swimmers to sign up in order to be cost effective.Last year's data showed that during 8 swim sessions the average number of entry-level swimmers attending was 15.Suppose the instructor wants to conduct a hypothesis test and the alternative hypothesis is "the population mean is greater than 15"If the sample size is 5 $\sigma$ is known,and alpha = .01,the critical value of z is _______.
A)2.575
B)-2.575
C)2.33
D)-2.33
E)2.45

Question

Quizplus · Accepted Answer

Since the alternative hypothesis is "the population mean is greater than 15," this is a one-tailed test. With a sample size of 5 and a known population standard deviation, we can use a z-test. With alpha = .01, the critical value of z for a one-tailed test to the right is 2.33. Therefore, the answer is C.

The Local Swim Team Is Considering Offering a New Semi-Private σ\sigmaσ

The Local Swim Team Is Considering Offering a New Semi-Private $\sigma$