Question 2(1 point)

Question 2 options:

An adviser is testing out a new online learning module for a placement test. They wish to test the claim that on average the new online learning module increased placement scores at a significance level of = 0.05. For the context of this problem, _D=_new-_oldwhere the first data set represents the new test scores and the second data set represents old test scores. Assume the population is normally distributed.

H₀: _D= 0

H₁: _D< 0

You obtain the following paired sample of 19 students that took the placement test before and after the learning module:

New LM

Old LM

57.1

55.8

58.3

51.7

83.6

76.6

50.5

47.5

51.5

48.6

20.6

15.5

35.2

29.9

46.7

54

23.5

21

48.8

58.5

53.1

42.6

76.6

61.2

29.6

26.3

14.5

11.4

43.7

56.3

57

46.1

66.1

72.9

38.1

43.2

44.4

51.1

Find the p-value. Round answer to 4 decimal places.

p-value =

Question 3(1 point)

Question 3 options:

A car insurance company suspects that the younger the driver is, the more reckless a driver he/she is. They take a survey and group their respondents based on age. Of 217 respondents between the ages of 16-25 (Group 1), 183 claimed to wear a seat belt at all times. Of 398 respondents who were 26+ years old (Group 2), 322 claimed to wear a seat belt at all times. Find a 95% confidence interval for the difference in proportions. Can it be concluded that there is a difference in the proportion of drivers who wear a seat belt at all times based on age group?

Enter the confidence interval - round to 3 decimal places.

<p₁-p₂<

Question 4(1 point)

Question 4 options:

TDaP is a booster shot that prevents Diphtheria, Tetanus, and Pertussis in adults and adolescents. It should be administered every 8 years for it to remain effective. A random sample of 550 people living in a town that experienced a pertussis outbreak this year were divided into two groups. Group 1 was made up of 145 individuals who had not had the TDaP booster in the past 8 years, and Group 2 consisted of 355 individuals who had. In Group 1, 18 individuals caught pertussis during the outbreak, and in Group 2, 13 individuals caught pertussis. Is there evidence to suggest that the proportion of individuals who caught pertussis and were not up to date on their booster shot is higher than those that were? Test at the 0.05 level of significance.

Enter the p-value - round to 5 decimal places.

p-value =

Question 5(1 point)

In clinical trials of a newly developed cold medicine, it was found that 45 out of 200 individuals that took the new medicine (Group 1) experienced an upset stomach as a side effect and 33 out of 150 individuals that took a placebo (Group 2) experienced an upset stomach. Test to see if the new drug produced a significantly higher proportion of individuals experiencing upset stomach. Use a 0.01 level of significance.

Select the correct alternative hypothesis and decision.

Question 5 options:

H₁:p₁p₂;Do not reject the null hypothesis.

H₁:p₁p₂;Reject the null hypothesis.

H₁:p₁>p₂;Do not reject the null hypothesis.

H₁:p₁>p₂;Reject the null hypothesis.

H₁:p₁<p₂;Do not reject the null hypothesis.

H₁:p₁<p₂;Reject the null hypothesis.

Question 7(1 point)

Results from previous studies showed 76% of all high school seniors from a certain city plan to attend college after graduation. A random sample of 200 high school seniors from this city reveals that 162 plan to attend college. Does this indicate that the percentage has increased from that of previous studies? Test at the 5% level of significance.

What is your conclusion?

Question 7 options:

Do not reject H₀. There is not enough evidence to support the claim that the proportion of students planning to go to college is greater than .76.

Cannot determine

More seniors are going to college

Reject H₀. There is enough evidence to support the claim that the proportion of students planning to go to college is now greater than .76.

Question 11(1 point)

An investor believes that investing in domestic and international stocks will give a difference in the mean rate of return. They take two random samples of 15 months over the past 30 years and find the following rates of return from a selection of domestic (Group 1) and international (Group 2) investments. Can they conclude that there is a difference at the 0.05 level of significance? Assume the data is normally distributed with unequal variances. Use a confidence interval method. Round to 4 decimal places.

Average Group 1 = 2.1234, SD Group 1 = 4.8765, n1 = 15

Average Group 2 = 3.0945, SD Group 2 = 5.1115, n2 = 15

___< ₁- ₂<___

___

Question 11 options:

Blank # 1

Blank # 2

Question 12(1 point)

An investor believes that investing in domestic and international stocks will give a difference in the mean rate of return. They take two random samples of 15 months over the past 30 years and find the following rates of return from a selection of domestic (Group 1) and international (Group 2) investments. Can they conclude that there is a difference at the 0.10 level of significance? Assume the data is normally distributed with unequal variances. Use a confidence interval method. Round to 4 decimal places.

Average Group 1 = 2.1234, SD Group 1 = 4.8765, n1 = 15

Average Group 2 = 3.0945, SD Group 2 = 5.1115, n2 = 15

___< ₁- ₂<___

___

Question 12 options:

Blank # 1

Blank # 2

Question 14(1 point)

In a random sample of 29 residents living in major cities on the West Coast (Group 1) and 29 residents living in major cities on the East Coast (Group 2), each individual was asked their age. The results can be seen in the table below. The population standard deviation of the age in West Coast cities is known to be 10.95 years and in East Coast cities is known to be 9.67 years. Assume the populations are normally distributed. Run a test at a 0.05 level of significance to test if west coast cities are, on average, older.

West Coast (Group 1)

East Coast (Group 2)

25

35

47

45

18

37

38

20

30

19

52

26

52

79

61

46

43

29

22

55

34

25

35

35

55

36

60

53

68

41

20

50

34

32

36

38

37

26

42

44

60

19

71

28

54

27

20

18

45

30

52

21

34

22

58

43

64

61

Enter the test statistic - round to 4 decimal places.

Test Statistic z =___

___

Question 14 options:

Question 16(1 point)

A researcher is curious if age makes a difference in whether or not students make use of the gym at a university. He takes a random sample of 30 days and counts the number of upperclassmen (Group 1) and underclassmen (Group 2) that use the gym each day. The data are below. The population standard deviation for underclassmen is known to be 22.57 and the population standard deviation for upperclassmen is known to be 13.57.

Upper Classmen average = 202.4, population SD = 13.57, n = 30

Under Classmen average = 191.3, population SD = 22.57, n = 30

Is there evidence to suggest that a difference exists in gym usage based on age? Construct a confidence interval for the data above to decide. Use=0.10.

Confidence Interval (round to 4 decimal places):

___< ₁- ₂<___

___

Question 16 options:

Blank # 1

Blank # 2

Question 17(1 point)

A physical therapist believes that at 30 years old adults begin to decline in flexibility and agility. To test this, he randomly samples 25 of his patients who are less than 30 years old and 27 of his patients are 30 or older and measures each patient's flexibility in the Sit-and-Reach test. Assume the populations are normally distributed. The results are below.

Less Than 30 (Group 1)

30 or Older (Group 2)

n

25

27

Mean Sit-and-Reach Score

20.21

18.99

Population Standard Dev. Sit-and-Reach Score

2.222

2.121

Is there evidence to suggest that adults under the age of 30 are more flexible?

Round to 4 decimal places. Make sure you put the 0 in front of the decimal.

Use=0.05.

p-value =___

___

Question 17 options:

Question 18(1 point)

According to the February 2008 Federal Trade Commission report on consumer fraud and identity theft, 23% of all complaints in 2007 were for identity theft. In that year, Alaska had 321 complaints of identity theft out of 1,432 consumer complaints. Does this data provide enough evidence to show that Alaska had a lower proportion of identity theft than 23%?

The hypotheses are:

H₀:p= 23%

H₁:p< 23%

What is a type I error in the context of this problem?

Reference: Federal Trade Commission, (2008). Consumer fraud and identity theft complaint data: January-December 2007. Retrieved from website: http://www.ftc.gov/opa/2008/02/fraud.pdf.

Question 18 options:

It is believed that more than 23% of Alaskans had identity theft and there really were 23% or more that experience identity theft.

It is believed that less than 23% of Alaskans had identity theft and there really were 23% or less that experienced identity theft.

It is believed that less than 23% of Alaskans had identity theft even though there really were 23% or more that experienced identity theft.

It is believed that more than 23% of Alaskans had identity theft even though there really were less than 23% that experienced identity theft.

Question 19(1 point)

Which of the following symbols represent a confidence level?

Question 19 options:

(1-)*100%

1-

Question 20(1 point)

Question 20 options:

The average age of an adult's first vacation without a parent or guardian was reported to be 23 years old. A travel agent believes that the average age is different from reported. They sample 28 adults and they asked their age in years when they first vacationed as an adult without a parent or guardian, data shown below. Test the claim using a 10% level of significance.

See Excel for Data.

adult vacation data.xlsx

The hypotheses for this problem are:

H0: = 23

H1: 23

Find the p-value. Round answer to 4 decimal places. p-value =