Question 854092
 In a test of the effectiveness of garlic for lowering cholesterol, 45 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 mf/dl) have a mean of 5.6 and standard deviation of 19.5
a. What is the best point estim ate of the population mean net change in LDL cholesterol after the garlic treatment?
Ans: 5.6 mf/dl
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b. Construct a 90% confidence interval of the mean net change in LDL cholesterol after the garlic treatment. 
ME = 1.645*19.5/sqrt(45) = 4.78
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90% CA:: 5.6-4.78 < u < 5.6+4.78
90%CA:: 0.82 < u < 10.38
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What does the confidence interval suggest about the effectiveness of garlic in reducing LDL cholesterol.
The mean is slightly higher than 5.6.
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Cheers,
Stan H.
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