Concept explainers
Find each.
a. zα/2 for the 99% confidence interval
b. zα/2 for the 98% confidence interval
c. zα/2 for the 95% confidence interval
d. zα/2 for the 90% confidence interval
e. zα/2 for the 94% confidence interval
(a)
To find: The value of
Answer to Problem 7E
The value of
Explanation of Solution
Given info:
The confidence level is 99%.
Calculation:
Since the 99% confidence interval is to be used.
Software procedure:
Step by step procedure to obtain the critical value using the MINITAB software:
- Choose Graph > Probability Distribution Plot choose View Probability > OK.
- From Distribution, choose ‘Normal’ distribution.
- Click the Shaded Area tab.
- Choose Probability Value and Both Tail for the region of the curve to shade.
- Enter the Probability value as 0.01.
- Click OK.
Output using the MINITAB software is given below:
From the output, the value of
(b)
To find: The value of
Answer to Problem 7E
The value of
Explanation of Solution
Given info:
The confidence level is 98%.
Calculation:
Critical value:
Since the 98% confidence interval is to be used.
Software procedure:
Step by step procedure to obtain the critical value using the MINITAB software:
- Choose Graph > Probability Distribution Plot choose View Probability > OK.
- From Distribution, choose ‘Normal’ distribution.
- Click the Shaded Area tab.
- Choose Probability Value and Both Tail for the region of the curve to shade.
- Enter the Probability value as 0.02.
- Click OK.
Output using the MINITAB software is given below:
From the output, the value of
(c)
To find: The value of
Answer to Problem 7E
The value of
Explanation of Solution
Given info:
The confidence level is 95%.
Calculation:
Critical value:
Since the 95% confidence interval is to be used.
Software procedure:
Step by step procedure to obtain the critical value using the MINITAB software:
- Choose Graph > Probability Distribution Plot choose View Probability> OK.
- From Distribution, choose ‘Normal’ distribution.
- Click the Shaded Area tab.
- Choose Probability Value and Both Tail for the region of the curve to shade.
- Enter the Probability value as 0.05.
- Click OK.
Output using the MINITAB software is given below:
From the output, the value of
(d)
To find: The value of
Answer to Problem 7E
The value of
Explanation of Solution
Given info:
The confidence level is 90%.
Calculation:
Critical value:
Since the 90% confidence interval is to be used.
Software procedure:
Step by step procedure to obtain the critical value using the MINITAB software:
- Choose Graph > Probability Distribution Plot choose View Probability> OK.
- From Distribution, choose ‘Normal’ distribution.
- Click the Shaded Area tab.
- Choose Probability Value and Both Tail for the region of the curve to shade.
- Enter the Probability value as 0.10.
- Click OK.
Output using the MINITAB software is given below:
From the output, the value of
(e)
To find: The value of
Answer to Problem 7E
The value of
Explanation of Solution
Given info:
The confidence level is 94%.
Calculation:
Critical value:
Since the 94% confidence interval is to be used.
Software procedure:
Step by step procedure to obtain the critical value using the MINITAB software:
- Choose Graph > Probability Distribution Plot choose View Probability> OK.
- From Distribution, choose ‘Normal’ distribution.
- Click the Shaded Area tab.
- Choose Probability Value and Both Tail for the region of the curve to shade.
- Enter the Probability value as 0.06.
- Click OK.
Output using the MINITAB software is given below:
From the output, the value of
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Chapter 7 Solutions
ELEMENTARY STATISTICS: STEP BY STEP- ALE
- Glencoe Algebra 1, Student Edition, 9780079039897...AlgebraISBN:9780079039897Author:CarterPublisher:McGraw Hill