A null hypothesis is that the mean cholesterol level is 200 in a certain age group. The alternative is that the mean is not 200. Which of the following is the most significant evidence against the null and in favor of the alternative?
A) For a sample of n = 25, the sample mean is 220.
B) For a sample of n = 10, the sample mean is 220.
C) For a sample of n = 50, the sample mean is 180.
D) For a sample of n = 20, the sample mean is 180.

Question

Quizplus · Accepted Answer

Larger sample sizes provide more reliable evidence against the null hypothesis. A sample size of 50 with a mean significantly different from 200 (180 in this case) offers stronger evidence against the null hypothesis than the other options.

A Null Hypothesis Is That the Mean Cholesterol Level Is