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Light bulbs: samples size

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A quality engineer in a light bulb manufacturing factory is planning a study to estimate the average life of a large shipment of light bulbs. The engineer wants to estimate the average life within plus or minus 15 hours with 95 percent confidence.

Assuming a process standard deviation of 100 hours, determine the sample size for this study.

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Solution Summary

This solution goes through how to calculate sample sizes for light bulbs.

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