Question

a randomized comparative experiment tests whether a cholesterol medication lowers the overall blood pressure for male patients. the control group has ten male patients and the treatment group, which receives the medication, has 10 male patients. all patients started with a cholesterol level of 245 mg/dl.
cholesterol in mg/dl
control: 241, 243, 242, 245, 250, 248, 246, 245, 242, 247
treatment: 230, 225, 220, 218, 224, 240, 232, 221, 235, 224
did the cholesterol medication lower the cholesterol levels?
a. yes. the treatment group had a lower level of cholesterol overall.
b. yes. the control group had a lower level of cholesterol overall.
c. no. the treatment group had a higher level of cholesterol overall.
d. no. the treatment group had the same level of cholesterol overall.

Explanation:

Step1: Calculate control group mean

Sum control values: $241+243+242+245+250+248+246+245+242+247 = 2449$
Mean: $\frac{2449}{10} = 244.9$ mg/dL

Step2: Calculate treatment group mean

Sum treatment values: $230+225+220+218+224+240+232+221+235+224 = 2269$
Mean: $\frac{2269}{10} = 226.9$ mg/dL

Step3: Compare the two means

$226.9 < 244.9$, so the treatment group has a lower overall cholesterol level.

Answer:

a. Yes. The treatment group had a lower level of cholesterol overall.