Question

3)In a study of government financial aid for college students, it becomes necessary to estimate the percentage of full-time college students who earn a bachelors degree in four years or less.Find the sample size needed to estimate that percentage. Use a 0.03margin of error and use a confidence level of 95​%.Complete parts​ (a) through​ (c) below.

5)In a test of effectiveness of garlic for lowering cholesterol, 48 subjects were treated with garlic in a processed tablet form. Cholesterol levels were measured before and after the treatment. The changes in their levels of LDL cholesterol (in mg/dL) have a mean of 3.4 and a standard deviation of 15.9.Construct a 95% confidence interval estimate of the mean net change in LDL cholesterol after the garlic treatment. What does the confidence interval suggest about the effectiveness of garlic in reducing LDL cholesterol?

What is the confidence interval estimate of the population mean muμ​?

__mg/dLl<u<__​mg/dL

​(Round to two decimal places as​ needed.)

What does the confidence interval suggest about the effectiveness of the​ treatment?

A.The confidence interval limits contain ​0, suggesting that the garlic treatment did not affect the LDL cholesterol levels.

B.The confidence interval limits contain 0, suggesting that the garlic treatment did affect the LDL cholesterol levels.

C.The confidence interval limits

do not contain ​0, suggesting that the garlic treatment

did not affect the LDL cholesterol levels.

D.The confidence interval limits do not contain ​0, suggesting that the garlic treatment did affect the LDL cholesterol levels.

Answer 1

The statistical software output for this problem is:

Hence,

95% confidence interval will be:

-1.22 < < 8.02

The confidence interval limits contain ​0, suggesting that the garlic treatment did not affect the LDL cholesterol levels. Option A is correct.