Obstacle Course Times An obstacle course was set up on a campus, and 12 volunteers were given a chance to complete it while they were being timed. They then sampled a new energy drink and were given the opportunity to run the course again. The "before" and "after" times in seconds are shown below. Is there sufficient evidence at a= 0.05 to conclude that the students did better the second time? Assume the variables are normally distributed. 1 2 3 4 5 6 7 8 9 10 11 12 Student Before 81 77 67 75 72 80 70 78 82 69 68 76 After 76 73 68 68 70 76 65 75 78 65 70 73 Send data to Excel Part: 0/5 Part 1 of 5 (a) State the hypotheses and identify the claim. Họ: (Choose one) H: (Choose one) This hypothesis test is a (Choose one) test.

MATLAB: An Introduction with Applications
6th Edition
ISBN:9781119256830
Author:Amos Gilat
Publisher:Amos Gilat
Chapter1: Starting With Matlab
Section: Chapter Questions
Problem 1P
icon
Related questions
Question
A ALEKS - Google Chrome
A www-awu.connectmath.com/alekscgi/x/Isl.exe/1cqJCkxOUkfU30pEIASLkB2_hW4nmFZxw4EDq4u2zFQT1HSdvxh.. Q
Sample Question
Obstacle Course Times An obstacle course was set up on a campus, and 11 volunteers were given a chance to complete it while they were being
timed. They then sampled a new energy drink and were given the opportunity to run the course again. The "before" and "after" times in seconds
are shown below. Is there sufficient evidence at a = 0.05 to conclude that the students did better the second time? Assume the variables are
normally distributed.
Student
1
3
4
8
9
10
11
Before
70
78
82
75
69
68
76
81
77
67
72
After
65
75
78
68
65
70
73
76
73
68
70
Send data to Excel
(a) State the hypotheses and identify the claim.
(b) Find the critical value(s).
(c) Compute the test value.
(d) Make the decision.
(e) Summarize the results.
Explanation
(a) State the hypotheses and identify the claim.
The null hypothesis H, is the statement that the difference between the matched pairs is zero. This is equivalent to un = 0.
The alternative hypothesis H, is the statement that there is a difference between the matched pairs. Since we are interested to see if the students
did better the second time (time before must be greater than time after), the differences must be greater than zero. This is equivalent to un >0.
The problem asks if "the students did better the second time." Hence, the claim is the alternative hypothesis H,.
(b) Find the critical value(s).
For n= 11, the degrees of freedom are d.f. = 11-1=10.
From OThe t Distribution Table, for a right-tailed test with a = 0.05 and d.f. = 10, the critical value is 1.812.
(c) Compute the test value.
First, make a table to find the differences of the values of the pairs of data, D, the square of the differences, D', and find the totals of D (E D) and
D(E D²).
Before (X)
After (X2)
Next, find the mean of the differences. D. snd the standard
D=X-X,
devistion of the differences. Sn
70
65
5
25
D =
78
75
3
9
34
82
78
4
16
- 3.091
75
68
7
49
nE D- (E D
n (n-1)
69
65
4
16
68
70
-2
4
11(174) - (34)
11 (11 - 1)
76
73
3
81
76
5
25
758
V 110
- 2.625
77
73
4
16
67
68
-1
1
Using the formula for the : test-for testing the difference
between two means-dependent samples, compute the test
valuer
72
70
2
4
Σ D= 34
ED = 174
Next, find the mean of the differences, D. and the standard deviation of the differences, Sn:
3.091 -0
2.625//11
ED
D =
- 3.905
Hence, the test value rounded to three decimal places is
-3.905
34
Transcribed Image Text:A ALEKS - Google Chrome A www-awu.connectmath.com/alekscgi/x/Isl.exe/1cqJCkxOUkfU30pEIASLkB2_hW4nmFZxw4EDq4u2zFQT1HSdvxh.. Q Sample Question Obstacle Course Times An obstacle course was set up on a campus, and 11 volunteers were given a chance to complete it while they were being timed. They then sampled a new energy drink and were given the opportunity to run the course again. The "before" and "after" times in seconds are shown below. Is there sufficient evidence at a = 0.05 to conclude that the students did better the second time? Assume the variables are normally distributed. Student 1 3 4 8 9 10 11 Before 70 78 82 75 69 68 76 81 77 67 72 After 65 75 78 68 65 70 73 76 73 68 70 Send data to Excel (a) State the hypotheses and identify the claim. (b) Find the critical value(s). (c) Compute the test value. (d) Make the decision. (e) Summarize the results. Explanation (a) State the hypotheses and identify the claim. The null hypothesis H, is the statement that the difference between the matched pairs is zero. This is equivalent to un = 0. The alternative hypothesis H, is the statement that there is a difference between the matched pairs. Since we are interested to see if the students did better the second time (time before must be greater than time after), the differences must be greater than zero. This is equivalent to un >0. The problem asks if "the students did better the second time." Hence, the claim is the alternative hypothesis H,. (b) Find the critical value(s). For n= 11, the degrees of freedom are d.f. = 11-1=10. From OThe t Distribution Table, for a right-tailed test with a = 0.05 and d.f. = 10, the critical value is 1.812. (c) Compute the test value. First, make a table to find the differences of the values of the pairs of data, D, the square of the differences, D', and find the totals of D (E D) and D(E D²). Before (X) After (X2) Next, find the mean of the differences. D. snd the standard D=X-X, devistion of the differences. Sn 70 65 5 25 D = 78 75 3 9 34 82 78 4 16 - 3.091 75 68 7 49 nE D- (E D n (n-1) 69 65 4 16 68 70 -2 4 11(174) - (34) 11 (11 - 1) 76 73 3 81 76 5 25 758 V 110 - 2.625 77 73 4 16 67 68 -1 1 Using the formula for the : test-for testing the difference between two means-dependent samples, compute the test valuer 72 70 2 4 Σ D= 34 ED = 174 Next, find the mean of the differences, D. and the standard deviation of the differences, Sn: 3.091 -0 2.625//11 ED D = - 3.905 Hence, the test value rounded to three decimal places is -3.905 34
Obstacle Course Times An obstacle course was set up on a campus, and 12 volunteers were given a chance to complete it while
they were being timed. They then sampled a new energy drink and were given the opportunity to run the course again. The
"before" and "after" times in seconds are shown below. Is there sufficient evidence at a= 0.05 to conclude that the students did
better the second time? Assume the variables are normally distributed.
1
2
3 4 5
6 7
8
9
10
11 12
Student
Before
81
77
67
75
72
80
70
78
82
69
68
76
After
76
73
68
68
70
76
65
75
78
65
70
73
Send data to Excel
Part: 0/5
Part 1 of 5
(a) State the hypotheses and identify the claim.
Họ:
(Choose one)
H:
(Choose one)
This hypothesis test is a (Choose one)
test.
Transcribed Image Text:Obstacle Course Times An obstacle course was set up on a campus, and 12 volunteers were given a chance to complete it while they were being timed. They then sampled a new energy drink and were given the opportunity to run the course again. The "before" and "after" times in seconds are shown below. Is there sufficient evidence at a= 0.05 to conclude that the students did better the second time? Assume the variables are normally distributed. 1 2 3 4 5 6 7 8 9 10 11 12 Student Before 81 77 67 75 72 80 70 78 82 69 68 76 After 76 73 68 68 70 76 65 75 78 65 70 73 Send data to Excel Part: 0/5 Part 1 of 5 (a) State the hypotheses and identify the claim. Họ: (Choose one) H: (Choose one) This hypothesis test is a (Choose one) test.
Expert Solution
trending now

Trending now

This is a popular solution!

steps

Step by step

Solved in 3 steps with 2 images

Blurred answer
Recommended textbooks for you
MATLAB: An Introduction with Applications
MATLAB: An Introduction with Applications
Statistics
ISBN:
9781119256830
Author:
Amos Gilat
Publisher:
John Wiley & Sons Inc
Probability and Statistics for Engineering and th…
Probability and Statistics for Engineering and th…
Statistics
ISBN:
9781305251809
Author:
Jay L. Devore
Publisher:
Cengage Learning
Statistics for The Behavioral Sciences (MindTap C…
Statistics for The Behavioral Sciences (MindTap C…
Statistics
ISBN:
9781305504912
Author:
Frederick J Gravetter, Larry B. Wallnau
Publisher:
Cengage Learning
Elementary Statistics: Picturing the World (7th E…
Elementary Statistics: Picturing the World (7th E…
Statistics
ISBN:
9780134683416
Author:
Ron Larson, Betsy Farber
Publisher:
PEARSON
The Basic Practice of Statistics
The Basic Practice of Statistics
Statistics
ISBN:
9781319042578
Author:
David S. Moore, William I. Notz, Michael A. Fligner
Publisher:
W. H. Freeman
Introduction to the Practice of Statistics
Introduction to the Practice of Statistics
Statistics
ISBN:
9781319013387
Author:
David S. Moore, George P. McCabe, Bruce A. Craig
Publisher:
W. H. Freeman