OpenStax, Statistics §8.1 A Single Population Mean Using the Normal Distribution · Try It 2 · Statistics · Normal distribution

A Single Population Mean Using the Normal Distribution · Try It 2

Suppose average pizza delivery times are normally distributed with an unknown population mean and a population standard deviation of 6 minutes. A random sample of 28 pizza delivery restaurants is taken and has a sample mean delivery time of 36 min.

Find a 90 percent confidence interval estimate for the population mean delivery time.

~5 minWritten answer · compare with the solution

OpenStax, Statistics · §8.1 A Single Population Mean Using the Normal Distribution · Try It 2

Stuck? A gentle nudge

No hints for this one.

Something off?

Workspace

Your working

Check your full solution

Upload photos of your handwritten work or a PDF, and Lemma will read it and tell you whether it's right — and where it first goes wrong if not.