# Constructing a 95% confidence interval for sample mean.

Dunkin Donuts advertises that a dozen of their donuts weighs about 43 oz. A certain baker has figured out that she can stay out of trouble with her manager if each donut weighs about 3.6 oz. To test her donut-making process, she randomly selects thirty-one donuts after baking and weighs them. The average of the sample is 3.504 oz with s = 0.109 oz. Construct a 95% confidence interval for the true population mean of donut weights, and then explain whether or not she will be in trouble.

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#### Solution Preview

Solution. From what you provided, we know that the size of sample is n=31, the mean of sample x^=3.504 and standard ...

#### Solution Summary

This problem involves finding the confidence interval for a sample mean of donut weights from dunkin donuts then determining if the advertised weight falls within those bounds.