In a certain factory they conducted a study to compare the mean productivity of the day...

In a certain factory they conducted a study to compare the mean productivity of the day shift workers with the mean productivity of the night shift workers. (The productivity is measured in units.)
A sample of 42 day shift workers gave a sample mean of 68, and a sample standard deviation of 15.
A sample of 33 night shift workers gave a sample mean of 63, and a sample standard deviation of 8.

(a) Obtain the 95% confidence interval for the difference between the means.

The 95% confidence interval is:

(b) At significance level 0.04, can we conclude that the two shifts really differ in terms of average productivity?

The test statistics =
Critical value =
Conclusion by critical value:
P-value =
The conclusion is (definite / borderline)

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Expert Solution

orchestra answered 2 years ago

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