a:
The test hypothesis.
a:
Explanation of Solution
The null hypothesis (H0) is
The t table value can be calculated as follows:
The t table value is 2.074.
The t value (t) can be calculated as follows:
The calculated t value is 0.43, and the p value is 0.6703. Since the p value is significantly different from 0, the alternate hypothesis is not accepted.
b:
The test hypothesis with increasing standard deviation.
b:
Explanation of Solution
The t table value can be calculated as follows:
The t table value is 2.074.
The t value (t) can be calculated as follows:
The calculated t value is 0.04, and the p value is 0.9716. Since the p value is significantly different from 0, the alternate hypothesis is not accepted.
c:
The impact of increasing standard deviation.
c:
Explanation of Solution
When the standard deviation increases, it reduces the calculated t value and increases the p value.
d:
The test hypothesis with increasing sample.
d:
Explanation of Solution
The t table value can be calculated as follows:
The t table value is 1.96.
The t value (t) can be calculated as follows:
The calculated t value is 1.53, and the p value is 0.1282. Since the p value is significantly different from 0, the alternate hypothesis is not accepted.
e:
The impact of increasing sample.
e:
Explanation of Solution
When the sample size increases, it increases the t value and reduces the p value.
f:
The test hypothesis with increasing mean value.
f:
Explanation of Solution
The t table value can be calculated as follows:
The t table value is 2.074.
The t value (t) can be calculated as follows:
The calculated t value is 0.72, and the p value is 0.4796. Since the p value is significantly different from 0, the alternate hypothesis is not accepted.
g:
The impact of increasing mean value.
g:
Explanation of Solution
When the mean increases, it increases the t value and reduces the p value.
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Chapter 13 Solutions
Statistics for Management and Economics (Book Only)
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