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A sample of 16 randomly chosen cylindrical shafts gave a mean diameter of x̄ = 30.45 mm


A sample of 16 randomly chosen cylindrical shafts gave a mean diameter of  x̄ = 30.45 mm. The standard deviation of the sample is s = 0.96 mm. Determine a 95% confidence interval for the mean diameter.

ans: 29.9385 < u < 30.9615

please show work


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