Question

3. Test the indicated claim about the means of two populations. Assume that the two samples are independent simple random samples selected from normally distributed populations. Do not assume that the population standard deviations are equal. Use the P-value method. A researcher wishes to determine whether people with high blood pressure can reduce their blood pressure, measured in mm Hg, by following a particular diet. Use a significance level of 0.01 to test the claim that the treatment group is from a population with a smaller mean than the control group. Treatment Group Control Group ni - 35 X1 - 189.1 n2 = 28 X2 203 51 - 38.7 52 - 392 4. Construct the indicated confidence interval for the difference between the two population means. Assume that the two samples are independent simple random samples selected from normally distributed populations. Do not assume that the population standard deviations are equal. A researcher was interested in comparing the amount of time spent watching television by women and by men. Independent simple random samples of 14 women and 17 men were selected, and each person was asked how many hours he or she had watched television during the previous week. The summary statistics are as follows. Construct a 99% confidence interval for HI - 42 the difference between the mean amount of time spent watching television for women and the mean amount of time spent watching television for men Women Men X1 - 126 hrs 2 - 140 kr 51 - 39 las 2 - 5 2 hus - 14 n2-17

Answer 1

B Di= 35 X = 189.1 S = 38.7 12=28 X2 = 203.7 52=39022 L=0.01. HO: 11 = 42 Hall<ll2 Test statistic n taon, the to = XI-X2 S12+S2² ni 52 to = -1,4773 pvalue= 0.0724 7 0.01 we accept. Ho at 0.01 los fe. There is not sufficient evidence to claim that treat- ment group is from population with smaller mean than control group 4) x1 = 12.6 X2=14 61 = 3.9 52=5.2 n=14 12=17 gg % confidence internal for all 1-12 is X1-x2) + 2221 n2 (12.6-14) £9,58(4.92+5:22) (-1.45 2.58* 2.6770) (-8.3067, 5. 5067)