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# Confidence Interval For Mean Price And Age Of Bank Employees

1. To find the confidence interval for the true mean of the "price in \$000" of all the employees in the bank, should the z-score or t-score be used?if so why?

2. Find a 95% and a 99% confidence level for "price in \$000" and "age" respectively using all the 80 data given that the population variance of the "price \$000" is 25 million and for "age" is 81. Write a brief report on your findings.

3. From the 80 data, take any 20 data and find a 95% confidence interval for "price in \$000" and "age" respectively. Report on your findings.

#### Solution Preview

Part 1. When the population variance is known, z-score is used to construct confidence intervals.
When the population variance is not known, t-score is used to construct confidence intervals.

It is important to note that, as ...

#### Solution Summary

This solution is comprised of detailed explanation on calculating confidence intervals. Also included is an explanation on when to use z-scores versus t-scores when calculating confidence intervals.

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