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z-score and 90% confidence interval

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1. The average hourly wage of workers at a fast food restaurant is $7.85 with a standard deviation of $0.35. Find the z value for each of the following pay rates.

a. $8.00
b. $7.50

2. A sample of 60 faculty members at a large university found that their average taxes were $500 a month, with a sample standard deviation of $35. What is the 90% confidence interval of the average taxes of all faculty members at the university?

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Solution Summary

The solution first shows how to calculate the z-score. It also shows how to construct the 90% confidence interval in detail.

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The average hourly wage of workers at a fast food restaurant is $7.85 with a standard deviation of $0.35. Find the z value for each of the following pay rates.

1. $8.00

2. $7.50

A sample of ...

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