When Engaging in Weight-Control (Fitness/fat Burning) Types of Exercise, a Person

When engaging in weight-control (fitness/fat burning) types of exercise, a person is expected to attain approximately 60% of his or her maximum heart rate. For 20-year-olds, this rate is approximately 120 bpm. A simple random sample of one hundred 20-year-olds was taken, and the sample mean was found to be 107 bpm, with a standard deviation of 45 bpm. Researchers wonder if this is evidence to conclude that the expected level is actually lower than 120 bpm. To determine this, we test the following hypotheses:
H₀: μ= 120 versus H_a: μ< 120
Suppose the mean and standard deviation obtained were based on a sample of size 25 rather than 100. How would the P-value change?

A) The P-value would be larger when using the smaller sample size.
B) The P-value would be smaller when using the smaller sample size.
C) The P-value would remain unchanged because the difference between x̄ and the hypothesized value μ= 120 is unchanged.
D) The P-value would remain unchanged because the variability measured by the standard deviation stays the same.