Question1

Suppose we want to show that only children have an average higher cholesterol level than the national average. It is known that the mean cholesterol level for all Americans is 190.

(i) Construct the relevant hypothesis test

(ii) We test 100 only children and find that average = 198 and suppose we know the population standard deviation s = 15.

Do we have evidence to suggest that only children have an average higher cholesterol level than the national average?

Question 2.

50 smokers were questioned about the number of hours they sleep each day. We want to test the hypothesis that smokers need less sleep than the general public, which needs an average of 7.7 hours of sleep.

(i) Construct the relevant hypothesis test

(ii) Compute a rejection region for a significance level of .05

(iii) If the sample mean is 7.5 and the population standard deviation is 0.5, what can you conclude?