A random sample of 25 rats was fed a diet for a period of 4 weeks. The weight gain (in grams) was recorded for each rat. It is known that the population variance is 4. The average weight gain was 16.1.
The P-value for testing the claim that this diet would increase weight by at least 15 grams would be
A) 0.005
B) 0.003
C) 0.014
D) 0.135

Question

Quizplus · Accepted Answer

The test statistic is calculated using the formula for a one-sample z-test. With a sample mean of 16.1, a population mean of 15, a population variance of 4, and a sample size of 25, the z-score is 2.75. The P-value corresponding to this z-score for a one-tailed test is approximately 0.014.

A Random Sample of 25 Rats Was Fed a Diet