(a)
The appropriate null and alternate hypotheses.
(a)
Answer to Problem 14E
Null hypothesis:
That is,
Alternative hypothesis:
That is less than
Explanation of Solution
Given information:
In a survey of random
Based on the survey an economist claims that less than
Calculation:
Based on the survey an economist claims that less than
So null and alternate hypotheses would be given as-
Null hypothesis:
That is,
Alternative hypothesis:
That is less than
(b)
The test statistic
(b)
Answer to Problem 14E
Explanation of Solution
Given information:
In a survey of random
Based on the survey an economist claims that less than
Formula used:
Calculation:
In a survey of random
Based on the survey an economist claims that less than
So the sample proportion
Compute the test statistic
Thus, the value of test statistic is
(c)
Whether the claim made by economist is true for
(c)
Answer to Problem 14E
The economist's claim is true.
Explanation of Solution
Given information:
In a survey of random
Based on the survey an economist claims that less than
Calculation:
Obtain the critical value.
Here, the test is left-tailed and the level of significance,
From Table
Rejection rule for left-tailed test:
If
Conclusion for
The value of test statistic is
Here, the value of test statistic is lesser than the critical value.
That is
Hence, the null hypothesis is rejected.
Thus it can be concluded that less than
(d)
Whether the claim made by economist is true for
(d)
Answer to Problem 14E
The executive claim is true.
Explanation of Solution
Given information:
In a survey of random
Based on the survey an economist claims that less than
Calculation:
Obtain the critical value.
Here, the test is left-tailed and the level of significance,
From Table
Rejection rule for left-tailed test:
If
Conclusion for
The value of test statistic is
Here, the value of test statistic is lesser than the critical value.
That is
Hence, the null hypothesis is rejected.
Thus it can be concluded that less than
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Chapter 9 Solutions
Elementary Statistics 2nd Edition
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