# Calculating the confidence interval for mean

A bolt manufacturer grabs 5 bolts from his production line and measures them. The results are 102mm, 101mm, 101mm, 95mm, and 106mm. What is the lower bound for the 95% confidence interval for the mean bolt length?

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Mean = (102+101+101+95+106)/5=101

Standard Deviation = square root of (sum of square of deviations from mean/n-1)

= ...

#### Solution Summary

The expert explains with formula and calculations how to calculate the confidence interval for mean.

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