Question

We would like to conduct a hypothesis test to determine whether the true mean pulse rate of healthy adults differs from 75 beats per minute. Pulse rates of healthy adults are known to follow a normal distribution with standard deviation 10 beats per minutes. We will record the pulse rates of a random sample of 15 healthy adults. It is decided that that null hypothesis will be rejected if X≤ 70.146 or X ≥ 79.854. What is the approximate significance level of the test?

a. 0.02
b. 0.03
c. 0.04
d. 0.05
e. 0.06