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Normal Distribution: Mean Labor Cost to Repair a Heat Pump

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A recent article in the Cincinnati Enquirer reported that the mean labor cost to repair a heat pump is $90 with a standard deviation of $22. Monte's Plumbing and Heating Service completed repairs on two heat pumps this morning. The labor cost for the first was $75 and it was $100 for the second. Compute z values for each and comment on your findings.

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The first z-value is negative because the value of x = 75 is less than the mean ...

Solution Summary

This solution provides the appropriate formulas and a step by step methodology, with the calculations formatted, in the attached Word document. An interpretation of the z-values is also given.

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