# The weights of a random sample of 121 women between the ages of 25

1. The weights of a random sample of 121 women between the ages of 25 and 34 had a standard deviation of 28 pounds. The weights of 121 women between the ages of 55 and 64 had a standard deviation 21 pounds. Test the claim that the older women are from a population with a standard deviation less than that for women in the 25 to 34 age group. Use er women are from a population with a standard deviation less than that for women in the 25 to 34 age group. Use α = 0.05.

(5 pts) Show all work!

a) _________________ ______________________

b) Critical value = _______

c) Rejection region ________________

d) Test statistic F = ____________

e) Should you reject your null hypothesis or fail to reject your null hypothesis? _______________________

2. Perform the indicated one-way ANOVA test. Assume that the population is normally distributed and that the population variance are equal. Test the claim that the populations have the same mean. Use α = 0.05. (6 pts) Show all work!

Brand 1

Brand 2

Brand 3

n=8

n=8

n=8

x = = 3.0

x = = 2.6

x = = 2.6

=0.50

=0.60

=0.55

=0.25

=0.36

=0.3025

a) _________________ ______________________

b) Critical value = _______

c) Rejection region ________________

d) Test statistic

a. x = ____________

b. M= ___________

c. M= ___________

d. F = _________

e) Should you reject your null hypothesis or fail to reject your null hypothesis? _______________________

3. Perform the indicated sign test. A convenience store owner believes that the median number of lottery tickets sold per day is 44. A random sample of 20 days yields the data below. Test the owner’s claim. Use α = 0.05. (3 pts) Show all work!

27 43 54 59 26 50 65 22 28 33

42 49 49 39 39 44 44 54 49 33

a) _________________ ______________________

b) Critical value _______

c) Test statistic __________

4. Nine students took the SAT test. Their scores are listed below. Later on, they took a test preparation course and retook the SAT. Their new scores are listed below. Use the Wilcoxon signed-rank test to find the test statistic to test the claim that the test preparation had no effect on their scores. Use α = 0.05. (2 pts)

Student

1

2

3

4

5

6

7

8

9

Before score

820

920

810

1180

1060

1100

990

850

1150

After score

840

920

800

1220

1090

1100

980

890

1170

Test statistic ___________

5. Minitab – Exercise 12 page 567 (Provide a copy of your Session window)

Open worksheet in Blackboard Module l6. The data for the four different regions of the United States should be in C1-C4. To perform a one-way analysis of variance, click on Stat/ANOVA/One-Way. In the top down-down, select “Response data re in a separate column for each factor level”. Select all four columns for the Responses and click on OK. The results of the test will be in the Session Window. (4 pts)

What can you conclude about the average number of days spent in a hospital? ________

Is it the same for all four regions of the United States? ______________