# statistics

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In order to test a new production method, 36 employees were selected randomly to try the new method. The mean was 75.79 parts per hour with a standard deviation of 28.25 parts per hour.

Calculate a 95% confidence interval for the true mean production rate for the new method.

• statistics -

95% = mean ± 1.96 SEm

SEm = SD/√n

You can do the calculations.

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