Online testing: Do you prefer taking tests on paper or online? A college instructor gave identical tests to two randomly sampled groups of 35 students. One group took the test on paper and the other took it online. Following are the test scores. Construct a 95% confidence interval for the difference in mean scores between paper and online tests. The instructor claims that the mean scores are the same for both the paper and the online versions of the test. Does the confidence Interval contradict this claim?

Question

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Answer 1

Textbook Question

Chapter 10.1, Problem 25E

Online testing: Do you prefer taking tests on paper or online? A college instructor gave identical tests to two randomly sampled groups of 35 students. One group took the test on paper and the other took it online. Following are the test scores.

Chapter 10.1, Problem 25E, Online testing: Do you prefer taking tests on paper or online? A college instructor gave identical

Construct a 95% confidence interval for the difference in mean scores between paper and online tests.
The instructor claims that the mean scores are the same for both the paper and the online versions of the test. Does the confidence Interval contradict this claim?

Definition Definition Measure of central tendency that is the average of a given data set. The mean value is evaluated as the quotient of the sum of all observations by the sample size. The mean, in contrast to a median, is affected by extreme values. Very large or very small values can distract the mean from the center of the data. Arithmetic mean: The most common type of mean is the arithmetic mean. It is evaluated using the formula: μ = 1 N ∑ i = 1 N x i Other types of means are the geometric mean, logarithmic mean, and harmonic mean. Geometric mean: The nth root of the product of n observations from a data set is defined as the geometric mean of the set: G = x 1 x 2 ... x n n Logarithmic mean: The difference of the natural logarithms of the two numbers, divided by the difference between the numbers is the logarithmic mean of the two numbers. The logarithmic mean is used particularly in heat transfer and mass transfer. ln x 2 − ln x 1 x 2 − x 1 Harmonic mean: The inverse of the arithmetic mean of the inverses of all the numbers in a data set is the harmonic mean of the data. 1 1 x 1 + 1 x 2 + ...

a.

Expert Solution

To determine

To find: The 95% confidence interval for the difference in mean scores between paper and online test.

Answer to Problem 25E

The 95% confidence interval for the difference in mean scores between paper and online test is (−7.91,2.08) .

Explanation of Solution

Given information:

The data is,

Paper
79	75	49	78	73	81	70
63	79	65	60	74	64	64
74	69	57	65	61	58	92
71	69	66	71	68	67	81
78	80	76	67	49	56	45

Online
79	75	71	81	56	72	49
75	63	81	74	72	71	73
83	59	78	65	53	47	63
82	81	76	65	82	78	76
65	72	85	84	81	so	79

Concept used:

Minitab is used.

Calculation:

The steps for the confidence interval are,

Import the data, select start and choose the basic statistics option then select the 2 sample t and enter summarized data.

Click option button choose confidence level, test difference and alternative hypothesis and then click ok.

The data is shown below.

Elementary Statistics 2nd Edition, Chapter 10.1, Problem 25E

Figure-1

Therefore, the 95% confidence interval for the difference in mean scores between paper and online test is (−7.91,2.08) .

b.

Expert Solution

To determine

To find: Whether the confident interval contradict the claim.

Answer to Problem 25E

The confident interval does not contradict the claim

Explanation of Solution

Given information:

The data is,

Paper
79	75	49	78	73	81	70
63	79	65	60	74	64	64
74	69	57	65	61	58	92
71	69	66	71	68	67	81
78	80	76	67	49	56	45

Online
79	75	71	81	56	72	49
75	63	81	74	72	71	73
83	59	78	65	53	47	63
82	81	76	65	82	78	76
65	72	85	84	81	so	79

Concept used:

Minitab is used.

Calculation:

Since, the 95% confidence interval for the difference in mean scores between paper and online test is (−7.91,2.08) and it include 0 .

Therefore, the confident interval does not contradict the claim.

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Answer 2

Textbook Question

Chapter 10.1, Problem 25E

Online testing: Do you prefer taking tests on paper or online? A college instructor gave identical tests to two randomly sampled groups of 35 students. One group took the test on paper and the other took it online. Following are the test scores.

Chapter 10.1, Problem 25E, Online testing: Do you prefer taking tests on paper or online? A college instructor gave identical

Construct a 95% confidence interval for the difference in mean scores between paper and online tests.
The instructor claims that the mean scores are the same for both the paper and the online versions of the test. Does the confidence Interval contradict this claim?

Definition Definition Measure of central tendency that is the average of a given data set. The mean value is evaluated as the quotient of the sum of all observations by the sample size. The mean, in contrast to a median, is affected by extreme values. Very large or very small values can distract the mean from the center of the data. Arithmetic mean: The most common type of mean is the arithmetic mean. It is evaluated using the formula: μ = 1 N ∑ i = 1 N x i Other types of means are the geometric mean, logarithmic mean, and harmonic mean. Geometric mean: The nth root of the product of n observations from a data set is defined as the geometric mean of the set: G = x 1 x 2 ... x n n Logarithmic mean: The difference of the natural logarithms of the two numbers, divided by the difference between the numbers is the logarithmic mean of the two numbers. The logarithmic mean is used particularly in heat transfer and mass transfer. ln x 2 − ln x 1 x 2 − x 1 Harmonic mean: The inverse of the arithmetic mean of the inverses of all the numbers in a data set is the harmonic mean of the data. 1 1 x 1 + 1 x 2 + ...

a.

Expert Solution

To determine

To find: The 95% confidence interval for the difference in mean scores between paper and online test.

Answer to Problem 25E

The 95% confidence interval for the difference in mean scores between paper and online test is (−7.91,2.08) .

Explanation of Solution

Given information:

The data is,

Paper
79	75	49	78	73	81	70
63	79	65	60	74	64	64
74	69	57	65	61	58	92
71	69	66	71	68	67	81
78	80	76	67	49	56	45

Online
79	75	71	81	56	72	49
75	63	81	74	72	71	73
83	59	78	65	53	47	63
82	81	76	65	82	78	76
65	72	85	84	81	so	79

Concept used:

Minitab is used.

Calculation:

The steps for the confidence interval are,

Import the data, select start and choose the basic statistics option then select the 2 sample t and enter summarized data.

Click option button choose confidence level, test difference and alternative hypothesis and then click ok.

The data is shown below.

Elementary Statistics 2nd Edition, Chapter 10.1, Problem 25E

Figure-1

Therefore, the 95% confidence interval for the difference in mean scores between paper and online test is (−7.91,2.08) .

b.

Expert Solution

To determine

To find: Whether the confident interval contradict the claim.

Answer to Problem 25E

The confident interval does not contradict the claim

Explanation of Solution

Given information:

The data is,

Paper
79	75	49	78	73	81	70
63	79	65	60	74	64	64
74	69	57	65	61	58	92
71	69	66	71	68	67	81
78	80	76	67	49	56	45

Online
79	75	71	81	56	72	49
75	63	81	74	72	71	73
83	59	78	65	53	47	63
82	81	76	65	82	78	76
65	72	85	84	81	so	79

Concept used:

Minitab is used.

Calculation:

Since, the 95% confidence interval for the difference in mean scores between paper and online test is (−7.91,2.08) and it include 0 .

Therefore, the confident interval does not contradict the claim.

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Answer 3

Textbook Question

Chapter 10.1, Problem 25E

Online testing: Do you prefer taking tests on paper or online? A college instructor gave identical tests to two randomly sampled groups of 35 students. One group took the test on paper and the other took it online. Following are the test scores.

Chapter 10.1, Problem 25E, Online testing: Do you prefer taking tests on paper or online? A college instructor gave identical

Construct a 95% confidence interval for the difference in mean scores between paper and online tests.
The instructor claims that the mean scores are the same for both the paper and the online versions of the test. Does the confidence Interval contradict this claim?

Definition Definition Measure of central tendency that is the average of a given data set. The mean value is evaluated as the quotient of the sum of all observations by the sample size. The mean, in contrast to a median, is affected by extreme values. Very large or very small values can distract the mean from the center of the data. Arithmetic mean: The most common type of mean is the arithmetic mean. It is evaluated using the formula: μ = 1 N ∑ i = 1 N x i Other types of means are the geometric mean, logarithmic mean, and harmonic mean. Geometric mean: The nth root of the product of n observations from a data set is defined as the geometric mean of the set: G = x 1 x 2 ... x n n Logarithmic mean: The difference of the natural logarithms of the two numbers, divided by the difference between the numbers is the logarithmic mean of the two numbers. The logarithmic mean is used particularly in heat transfer and mass transfer. ln x 2 − ln x 1 x 2 − x 1 Harmonic mean: The inverse of the arithmetic mean of the inverses of all the numbers in a data set is the harmonic mean of the data. 1 1 x 1 + 1 x 2 + ...

a.

Expert Solution

To determine

To find: The 95% confidence interval for the difference in mean scores between paper and online test.

Answer to Problem 25E

The 95% confidence interval for the difference in mean scores between paper and online test is (−7.91,2.08) .

Explanation of Solution

Given information:

The data is,

Paper
79	75	49	78	73	81	70
63	79	65	60	74	64	64
74	69	57	65	61	58	92
71	69	66	71	68	67	81
78	80	76	67	49	56	45

Online
79	75	71	81	56	72	49
75	63	81	74	72	71	73
83	59	78	65	53	47	63
82	81	76	65	82	78	76
65	72	85	84	81	so	79

Concept used:

Minitab is used.

Calculation:

The steps for the confidence interval are,

Import the data, select start and choose the basic statistics option then select the 2 sample t and enter summarized data.

Click option button choose confidence level, test difference and alternative hypothesis and then click ok.

The data is shown below.

Elementary Statistics 2nd Edition, Chapter 10.1, Problem 25E

Figure-1

Therefore, the 95% confidence interval for the difference in mean scores between paper and online test is (−7.91,2.08) .

b.

Expert Solution

To determine

To find: Whether the confident interval contradict the claim.

Answer to Problem 25E

The confident interval does not contradict the claim

Explanation of Solution

Given information:

The data is,

Paper
79	75	49	78	73	81	70
63	79	65	60	74	64	64
74	69	57	65	61	58	92
71	69	66	71	68	67	81
78	80	76	67	49	56	45

Online
79	75	71	81	56	72	49
75	63	81	74	72	71	73
83	59	78	65	53	47	63
82	81	76	65	82	78	76
65	72	85	84	81	so	79

Concept used:

Minitab is used.

Calculation:

Since, the 95% confidence interval for the difference in mean scores between paper and online test is (−7.91,2.08) and it include 0 .

Therefore, the confident interval does not contradict the claim.

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Subscribe now to access step-by-step solutions to millions of textbook problems written by subject matter experts!

Answer 4

Textbook Question

Chapter 10.1, Problem 25E

Online testing: Do you prefer taking tests on paper or online? A college instructor gave identical tests to two randomly sampled groups of 35 students. One group took the test on paper and the other took it online. Following are the test scores.

Chapter 10.1, Problem 25E, Online testing: Do you prefer taking tests on paper or online? A college instructor gave identical

Construct a 95% confidence interval for the difference in mean scores between paper and online tests.
The instructor claims that the mean scores are the same for both the paper and the online versions of the test. Does the confidence Interval contradict this claim?

Definition Definition Measure of central tendency that is the average of a given data set. The mean value is evaluated as the quotient of the sum of all observations by the sample size. The mean, in contrast to a median, is affected by extreme values. Very large or very small values can distract the mean from the center of the data. Arithmetic mean: The most common type of mean is the arithmetic mean. It is evaluated using the formula: μ = 1 N ∑ i = 1 N x i Other types of means are the geometric mean, logarithmic mean, and harmonic mean. Geometric mean: The nth root of the product of n observations from a data set is defined as the geometric mean of the set: G = x 1 x 2 ... x n n Logarithmic mean: The difference of the natural logarithms of the two numbers, divided by the difference between the numbers is the logarithmic mean of the two numbers. The logarithmic mean is used particularly in heat transfer and mass transfer. ln x 2 − ln x 1 x 2 − x 1 Harmonic mean: The inverse of the arithmetic mean of the inverses of all the numbers in a data set is the harmonic mean of the data. 1 1 x 1 + 1 x 2 + ...

a.

Expert Solution

To determine

To find: The 95% confidence interval for the difference in mean scores between paper and online test.

Answer to Problem 25E

The 95% confidence interval for the difference in mean scores between paper and online test is (−7.91,2.08) .

Explanation of Solution

Given information:

The data is,

Paper
79	75	49	78	73	81	70
63	79	65	60	74	64	64
74	69	57	65	61	58	92
71	69	66	71	68	67	81
78	80	76	67	49	56	45

Online
79	75	71	81	56	72	49
75	63	81	74	72	71	73
83	59	78	65	53	47	63
82	81	76	65	82	78	76
65	72	85	84	81	so	79

Concept used:

Minitab is used.

Calculation:

The steps for the confidence interval are,

Import the data, select start and choose the basic statistics option then select the 2 sample t and enter summarized data.

Click option button choose confidence level, test difference and alternative hypothesis and then click ok.

The data is shown below.

Elementary Statistics 2nd Edition, Chapter 10.1, Problem 25E

Figure-1

Therefore, the 95% confidence interval for the difference in mean scores between paper and online test is (−7.91,2.08) .

b.

Expert Solution

To determine

To find: Whether the confident interval contradict the claim.

Answer to Problem 25E

The confident interval does not contradict the claim

Explanation of Solution

Given information:

The data is,

Paper
79	75	49	78	73	81	70
63	79	65	60	74	64	64
74	69	57	65	61	58	92
71	69	66	71	68	67	81
78	80	76	67	49	56	45

Online
79	75	71	81	56	72	49
75	63	81	74	72	71	73
83	59	78	65	53	47	63
82	81	76	65	82	78	76
65	72	85	84	81	so	79

Concept used:

Minitab is used.

Calculation:

Since, the 95% confidence interval for the difference in mean scores between paper and online test is (−7.91,2.08) and it include 0 .

Therefore, the confident interval does not contradict the claim.

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Subscribe now to access step-by-step solutions to millions of textbook problems written by subject matter experts!

Answer 5

Textbook Question

Answer 6

Textbook Question

Answer 7

a.

Expert Solution

To determine

To find: The 95% confidence interval for the difference in mean scores between paper and online test.

Answer to Problem 25E

The 95% confidence interval for the difference in mean scores between paper and online test is (−7.91,2.08) .

Explanation of Solution

Given information:

The data is,

Paper
79	75	49	78	73	81	70
63	79	65	60	74	64	64
74	69	57	65	61	58	92
71	69	66	71	68	67	81
78	80	76	67	49	56	45

Online
79	75	71	81	56	72	49
75	63	81	74	72	71	73
83	59	78	65	53	47	63
82	81	76	65	82	78	76
65	72	85	84	81	so	79

Concept used:

Minitab is used.

Calculation:

The steps for the confidence interval are,

Import the data, select start and choose the basic statistics option then select the 2 sample t and enter summarized data.

Click option button choose confidence level, test difference and alternative hypothesis and then click ok.

The data is shown below.

Elementary Statistics 2nd Edition, Chapter 10.1, Problem 25E

Figure-1

Therefore, the 95% confidence interval for the difference in mean scores between paper and online test is (−7.91,2.08) .

b.

Expert Solution

To determine

To find: Whether the confident interval contradict the claim.

Answer to Problem 25E

The confident interval does not contradict the claim

Explanation of Solution

Given information:

The data is,

Paper
79	75	49	78	73	81	70
63	79	65	60	74	64	64
74	69	57	65	61	58	92
71	69	66	71	68	67	81
78	80	76	67	49	56	45

Online
79	75	71	81	56	72	49
75	63	81	74	72	71	73
83	59	78	65	53	47	63
82	81	76	65	82	78	76
65	72	85	84	81	so	79

Concept used:

Minitab is used.

Calculation:

Since, the 95% confidence interval for the difference in mean scores between paper and online test is (−7.91,2.08) and it include 0 .

Therefore, the confident interval does not contradict the claim.

Answer 8

a.

Expert Solution

To determine

To find: The 95% confidence interval for the difference in mean scores between paper and online test.

Answer to Problem 25E

The 95% confidence interval for the difference in mean scores between paper and online test is (−7.91,2.08) .

Explanation of Solution

Given information:

The data is,

Paper
79	75	49	78	73	81	70
63	79	65	60	74	64	64
74	69	57	65	61	58	92
71	69	66	71	68	67	81
78	80	76	67	49	56	45

Online
79	75	71	81	56	72	49
75	63	81	74	72	71	73
83	59	78	65	53	47	63
82	81	76	65	82	78	76
65	72	85	84	81	so	79

Concept used:

Minitab is used.

Calculation:

The steps for the confidence interval are,

Import the data, select start and choose the basic statistics option then select the 2 sample t and enter summarized data.

Click option button choose confidence level, test difference and alternative hypothesis and then click ok.

The data is shown below.

Elementary Statistics 2nd Edition, Chapter 10.1, Problem 25E

Figure-1

Therefore, the 95% confidence interval for the difference in mean scores between paper and online test is (−7.91,2.08) .

Answer 9

a.

Expert Solution

Answer 10

a.

Expert Solution

Answer 11

Expert Solution

Answer 12

To determine

To find: The 95% confidence interval for the difference in mean scores between paper and online test.

Answer 13

Answer to Problem 25E

The 95% confidence interval for the difference in mean scores between paper and online test is (−7.91,2.08) .

Answer 14

Explanation of Solution

Given information:

The data is,

Paper
79	75	49	78	73	81	70
63	79	65	60	74	64	64
74	69	57	65	61	58	92
71	69	66	71	68	67	81
78	80	76	67	49	56	45

Online
79	75	71	81	56	72	49
75	63	81	74	72	71	73
83	59	78	65	53	47	63
82	81	76	65	82	78	76
65	72	85	84	81	so	79

Concept used:

Minitab is used.

Calculation:

The steps for the confidence interval are,

Import the data, select start and choose the basic statistics option then select the 2 sample t and enter summarized data.

Click option button choose confidence level, test difference and alternative hypothesis and then click ok.

The data is shown below.

Elementary Statistics 2nd Edition, Chapter 10.1, Problem 25E

Figure-1

Therefore, the 95% confidence interval for the difference in mean scores between paper and online test is (−7.91,2.08) .

Answer 15

b.

Expert Solution

To determine

To find: Whether the confident interval contradict the claim.

Answer to Problem 25E

The confident interval does not contradict the claim

Explanation of Solution

Given information:

The data is,

Paper
79	75	49	78	73	81	70
63	79	65	60	74	64	64
74	69	57	65	61	58	92
71	69	66	71	68	67	81
78	80	76	67	49	56	45

Online
79	75	71	81	56	72	49
75	63	81	74	72	71	73
83	59	78	65	53	47	63
82	81	76	65	82	78	76
65	72	85	84	81	so	79

Concept used:

Minitab is used.

Calculation:

Since, the 95% confidence interval for the difference in mean scores between paper and online test is (−7.91,2.08) and it include 0 .

Therefore, the confident interval does not contradict the claim.

Answer 16

b.

Expert Solution

Answer 17

b.

Expert Solution

Answer 18

Expert Solution

Answer 19

To determine

To find: Whether the confident interval contradict the claim.

Answer 20

Answer to Problem 25E

The confident interval does not contradict the claim

Answer 21

Explanation of Solution

Given information:

The data is,

Paper
79	75	49	78	73	81	70
63	79	65	60	74	64	64
74	69	57	65	61	58	92
71	69	66	71	68	67	81
78	80	76	67	49	56	45

Online
79	75	71	81	56	72	49
75	63	81	74	72	71	73
83	59	78	65	53	47	63
82	81	76	65	82	78	76
65	72	85	84	81	so	79

Concept used:

Minitab is used.

Calculation:

Since, the 95% confidence interval for the difference in mean scores between paper and online test is (−7.91,2.08) and it include 0 .

Therefore, the confident interval does not contradict the claim.

Answer 22

Ch. 10.1 - In Exercises 5 and 6, fill in each blank with e...Ch. 10.1 - In Exercises 5 and 6, fill in each blank with e...Ch. 10.1 - Prob. 7E Ch. 10.1 - Prob. 8E Ch. 10.1 - In Exercises 9-14, construct the confidence...Ch. 10.1 - Prob. 10E Ch. 10.1 - In Exercises 9-14, construct the confidence...Ch. 10.1 - Prob. 12E Ch. 10.1 - Prob. 13E Ch. 10.1 - Prob. 14E

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Answer to Problem 25E

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Answer to Problem 25E

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Chapter 10 Solutions