1. In a study of marital satisfaction, a random sample of 12 couples married for between five and fifteen years was obtained. Each couple was interviewed by the researcher and rated on a Marital Cohesion (MC) scale.

Couple #	MC	MC2
#1	14	196
#2	9	81
#3	7	49
#4	14	196
#5	15	225
#6	13	169
#7	10	100
#8	17	289
#9	11	121
#10	18	324
#11	14	196
#12	14	196
Totals	X= 156	(X2) = 2142

a. Calculate the sample mean of Marital Cohesion? (Round to the nearest hundredth if it is necessary.)

2. Calculate the Estimated Population standard deviation of marital Cohesion? (Round to the nearest hundredths if it is necessary).

3.Is there a significant difference between the sample mean of Marital Cohesion and the population mean of 15and level of .10? Carry out all 9 steps of the hypothesis testing.

4. In studying the effect of a drug for treating patients with respiratory problems, the researcher found the those who didn't take the drug had an overall mean of 3.35 in the respiratory scores with a standard deviation of .08. The researcher obtained a sample of 12 consenting patients, who, after discussion with their doctor, chose the same respiratory drug they would receive. Patients' respiratory tests were assessed twice over a two-month period after initiating the treatment and their results for the 2nd test are provided below.

Respiratory Test 2

3.4

3.4

3.3

3.4

3.3

3.3

3.3

3.2

3.2

3.2

3.2

3.3

X = 39.5

a. Calculate the sample mean of Respiratory scores. (Round to the nearest hundredth if it is necessary.)

5. b. Research Question: The researcher wants to know if there is a significant difference between average respiratory score of those who didn't take any drugs and the group who did in their second test?

Is there a difference between the two means at the significance level of .05? Carry out 9 steps of hypothesis testing.

6. While reading a published research report, the following is reported: "When we examined the critical skills data, the mean of 50.00 from the sample of 200 adolescents differed significantly from the population mean of 53.5, [t(199) = 3.54, p < .05]." a. What is the N?

7. b. What is the ?

8. c. What is the Tobt?

9. d. Find the Tcrits.

10. e. Can we reject or fail to reject the null hypothesis at the of .05? Explain your answer.

11. Does the sample mean differ significantly from the population meanat theof .05? Support your answer.