The average serum cholesterol level in a certain group of patients is 240 milligrams. The standard deviation is 18 milligrams. A new medication is designed to lower the cholesterol level if taken for one month. A sample of 40 people used the medication for 30 days, after which their average cholesterol level was 229 milligrams. Does the medication lower the cholesterol level of the patients?
a. Step 1: State the hypotheses.
b. Step 2: Calculate the Test Statistic.
c. Step 3: Find the P-value.
