A pharmaceutical company wishes to test a new drug with the expectation of lowering cholesterol levels. Ten subjects are randomly selected and pretested. The results are listed below. The subjects were placed on the drug for a period of 6 months, after which their cholesterol levels were tested again. The results are listed below. (All units are milligrams per deciliter.) Test the company’s claim that the drug lowers cholesterol levels. Assume the samples are random and dependent, and the populations are normally distributed. Use α = 0.05. Let μd= the before level minus the after level.

Subject 1 2 3 4 5 6 7 8 9 10

Before 195 225 205 195 175 250 235 268 189 240

After 180 220 210 175 177 250 205 251 190 225
What are the hypotheses?
What type of test should be performed?
What is the average difference and standard deviation of differences?
What is the test statistic?
What is the conclusion?