answer questions 36, 40.

for question 36:

36. Time Watching TV A recent study of 48 randomly selected children (ages 6-8) found that the mean length of time spent watching television each week was 12.95 hours and the standard deviation was 4.31 hours. The mean time 56 randomly selected children (ages 9-11) watched television each week was 15.02 hours and the standard deviation was 4.99 hours. At a = 0.05, test the claim that the mean time per week children ages 6-8 watch television is 2 hours less than that of children ages 9-11. (Adapted from University of Michigan's Institute for Social Research)40. Comparing Cancer Drugs TWO groups of patients with colorectal cancer are treated with a different drug. Group A's 140 patients are treated using> the drug Irinotecan and Group B's 127 patients are treated using the drug Fluorouracil. The mean number of months that Group A reported no cancer-related pain was 10. 3 and the standard deviation was 1.2. The mean number of months that Group B reported no cancer-related pain was 8.5 and the standard deviation was-1,5. Construct a 95% confidence interval for M1 M, where ,u.1 is the mean number of months that Group A reported no cancerrelated pain and M is the mean number of months that Group B reported no cancer-related pain. (Adapted from The Lancet) (a) identify the claim and state H0 and Ha, (b) use Table 4 in Appendix B to nd the critical value(s) and identify the rejection region(s), (c) nd the standardized test statistic 2:. (d) decide whether to reject or fail to reject the null hypothesis, and (e) interpret the decision in the context of the original claim. If convenient, use technology to solve the problem. In each exercise, assume the samples are randomly selected and that the samples are independent. Constructing Confidence Intervals for M1 - M2 You can construct confidence interval for the difference between two population means M - , by using the following if n 2 30 and n2 2 30, or both populations are normally distributed. Also, the samples must be randomly selected and independent. + 02