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Large sample confidence interval for a population mean

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A random sample of 56 fluorescent light bubs has a mean life of 645 hours with a standard deviation of 31 hours.

A) Construct a 95% confidence interval for the population

B) How would you increase the accuracy in this problem?

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This solution is a step-by-step example of a large sample confidence interval for a population mean.

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Confidence Interval using T or Z...
A random sample of 56 fluorescent light bulbs has a mean life of 645 hours with a standard deviation of 31 hours.

A) Construct a 95% confidence interval for the population

This is a large sample 95% confidence interval for a population mean so we use the Z ...

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