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⎯⎯⎯⎯X¯ ≤ 69.397 or X⎯⎯⎯⎯X¯ ≥ 80.603. What is the significance level of the test?

Question 11 options:

	0.02
	0.03
	0.04
	0.05
	0.06

Answer 1

We are to  determine whether  the true mean pulse rate of healthy adults differs from 75 beats per minute.

Also, pulse rates of healthy adults are known to follow a normal distribution with standard deviation 10 beats per minutes., i.e.

, where X is pulse rate.

So, our problem of testing is

We are given a random sample of 15 healthy adults, i.e.

So, the confidence interval is given by,

,where is the level of significance.

Then according to the question,

or

Now,

Then,

[Using Standard Normal Table]