3:

A consultant for a large company recommends an "employee athlete" program, encouraging every employee to devote 5 minutes an hour to physical activity. The evidence is shown in the results below. A small company, on hearing about the employee athlete program at the large Keystrokes per Hour company down the street, decides to try it as well. To measure the difference in productivity, they measure the average number of keystrokes Before After Difference per hour of 21 employees before and after the program is instituted. The data is shown to the right. Complete parts a through c. (After - Before) Mean 1505.2 1543.9 38.7 SD 156.8 130.7 119.9 N 21 21 21 Click the icon to view the results of the employee athlete program at the large company. O Ho: Hd = 0, HA: Hd 0, HA: Hd = 0 O Ho: Hd # 0, HA: Hd = 0 O Ho: Hd 0 Calculate the test statistic. 1=] (Round to two decimal places as needed.) X Calculate the P-value. Large company data P-value = (Round to three decimal places as needed.) The data from the employee athlete program for the Keystrokes per Hour large company is shown to the right. The larger What can you conclude? Assume a = 0.05. Choose the correct answer below. Difference company wanted to determine if the program changed keystrokes per hour. The data has a test Before After (After - Before) A. Reject Ho. There is sufficient evidence that the program increases productivity at the small company. statistic of 2.34, a P-value of 0.021, and a 95% Mean 1536.6 1559.4 22.8 confidence interval of (3.49, 42.11). The conclusion SD 167.8 148.1 111.3 O B. Reject Ho. There is insufficient evidence that the program increases productivity at the small company. is that there is sufficient evidence that the mean 130 130 number of keystrokes per hour has changed. 130 O C. Fail to reject Ho. There is sufficient evidence that the program increases productivity at the small company. O D. Fail to reject Ho. There is insufficient evidence that the program increases productivity at the small company. b) Give a 95% confidence interval for the mean change in productivity (as measured by keystrokes per hour). Print Done (Round to two decimal places as needed. )