OpenStax, Introductory Statistics 2e §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 six minutes. A random sample of 28 pizza delivery restaurants is taken and has a sample mean delivery time of 36 minutes.

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

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

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