Mathematics, 24.06.2019 23:40 angelinaranee15

The life in hours of a 75-watt light bulb is known to be normally distributed with σ= 27 hours. a random sample of 20 bulbs has a mean life of ¯x= 1012 hours. suppose that we wanted the margin of error in estimating the mean life from the two-sided confidence interval to be five hours at 95% confidence. what sample size should be used?

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The life in hours of a 75-watt light bulb is known to be normally distributed with σ= 27 hours. a ra...

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