In a test of the effectiveness of garlic for lowering cholesterol, 42 subjects were treated with garlic in a processed tabletform. Cholesterol levels were measured before and after the treatment. The changes (before-after) in their levels ofLDL cholesterol (in mg/dL) have a mean of 3.8 and a standard deviation of 18.7. Construct a 95% confidence intervalestimate of the mean net change in LDL cholesterol after the garlic treatment. What does the confidence intervalsuggest about the effectiveness of garlic in reducing LDL cholesterol?Click here to view at distribution table.Click here to view page 1 of the standard normal distribution table.Click here to view page 2 of the standard normal distribution table.What is the confidence interval estimate of the population mean μ?mg/dL <μ< mg/dL(Round to two decimal places as needed.)

The changes in the levels of LDL cholesterol have a mean of and a standard deviation of 18.7. The sample size is 42.Thus, x¯1−x¯2=3.8, sd=18.7, and n=42.Using excel formula "=T.INV.2T(0.05,41)", the t-value for 95% confidence level is 2.02. The 95% confidence interval estimate of the mean net change in LDL cholesterol after the garlic treatment is,The 95% confidence interval estimate of the mean net change in LDL cholesterol after the garlic treatment is −2.03mg/dL<μ<9.63mg/dL.The 95% confidence interval estimate of the mean net change in LDL cholesterol after the garlic treatment contain the value 0. This means, there is no difference in LDL cholesterol before and after the garlic treatment Thus, this confidence interval suggest that there is no effectiveness of garlic in reducing LDL cholesterol.The 95% confidence interval estimate of the mean net change in LDL cholesterol after the garlic treatment is −2.03mg/dL<μ<9.63mg/dL.The confidence interval suggest that there is no effectiveness of garlic in reducing LDL cholesterol.