The following table shows the golf scores of nine people before and after a lesson given by the golf professional at Pike Creek Golf Club. These data can also be found in the Excel file lessons.xlsx.

Golfer 1 2 3 4 5 6 7 8 9 Before lesson 96 88 94 86 102 90 100 90 99 After lesson 88 81 95 79 95 85 101 85 95

a. Using a = 0.05, test the professional’s claim that the average golfer will lower his or her score by more than two strokes after a lesson.

b. Approximate the p-value using Table 5 in Appendix A and interpret the result.

c. Construct a 90% confidence interval to estimate the average reduction in golf scores after the lesson. Interpret the results.

d. Verify your results using Excel’s Data Analysis. Mac users can rely on PHStat for this procedure.

e. Identify the p-value using Excel and interpret the result.

f. What assumptions need to be made in order to perform this procedure?

AppendixLO1