Engineering, 20.07.2019 03:20 lucy3964

To determine the efficiency of a batch of production of electric motors, 8 motors are tested. the average efficiency of the sample is calculated to be 88.5% and the standard deviation of the sample is 0.5 percentage point. (a) determine a 95% confidence interval for the mean efficiency of the (b) if we want to cut the confidence interval to one third, how many more motors should be tested?

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To determine the efficiency of a batch of production of electric motors, 8 motors are tested. the av...

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