In the introductory case to this chapter, the dean at a large university in California wonders if students at her university study less than the 1961 national average of 24 hours per week. She randomly selects 35 students and asks their average study time per week (in hours). From their responses (see Table 9.1) she calculates a sample mean of 16.37 hours and a sample standard deviation of 7.22 hours.

a. Specify the competing hypotheses to test the dean’s concern.

b. Calculate the value of the appropriate test statistic.

c. At a 5% significance level, specify the critical value(s) and the decision rule.

d. What is the conclusion to the hypothesis test? P-56