A researcher wanted to find the effect of a special diet on systolic blood pressure. She selected a sample of seven adults and put them on this dietary plan for three months. The following table gives the systolic blood pressure (in mm Hg) of these seven adults before and after the completion of this plan. Before: 210 180 195 220 231 199 224 After: 193 186 186 223 220 183 223 Let ?? be the mean reduction in the systolic blood pressures due to this special dietary plan for the population of all adults. Construct a 95% confidence interval for ??. Assume that the population of paired differences is (approximately) normally distributed.
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First, we need to find the differences in systolic blood pressure for each individual before and after the dietary plan. Differences (Before - After): 210 - 193 = 17 180 - 186 = -6 195 - 186 = 9 220 - 223 = -3 231 - 220 = 11 199 - 183 = 16 224 - 223 = 1 Show more…
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