3 For each case state the null and alternative hypothesis as

3. For each case, state the null and alternative hypothesis as done in class.

For example:

H0: 23

Ha: > 23

a) The average time workers spent commuting to work in Verona five years ago was 38.2 minutes. The Verona Chamber of Commerce asserts that the average is less now.

b) The mean salary for all men in a certain profession is $58,291. A special interest group thinks that the mean salary for women in the same profession is different.

c) The accepted figure for the caffeine content of an 8-ounce cup of coffee is 133 mg. A dietitian believes that the average for coffee served in a local restaurants is higher.

d) The average yield per acre for all types of corn in a recent year was 161.9 bushels. An economist believes that the average yield per acre is different this year.

e) An industry association asserts that the average age of all self-described fly fishermen is 42.8 years. A sociologist suspects that it is higher.

Solution

a)

Ho: u >= 38.2
Ha: u < 38.2

****************

b)

Ho: u = 58291
Ha: u =/= 58291

******************

c)

Ho: u <= 133
Ha: u > 133

*********************

d)

Ho: u = 161.9
Ha: u =/= 161.9

**********************

e)

Ho: u <= 42.8
Ha: u > 42.8