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OpenStax, Introductory Business Statistics 2e §8.1 A Confidence Interval When the Population Standard Deviation Is Known or Large Sample Size · Try It 3 · Statistics · Confidence intervals

A Confidence Interval When the Population Standard Deviation Is Known or Large Sample Size · Try It 3

Refer back to the pizza-delivery Try It 8.1 exercise. The mean delivery time is 36 minutes and the population standard deviation is six minutes. Assume the sample size is changed to 50 restaurants with the same sample mean. Find a 90% confidence interval estimate for the population mean delivery time.

This exercise builds on another exercise in its source book, which isn't shown here.

~5 minWritten answer · compare with the solution

OpenStax, Introductory Business Statistics 2e · §8.1 A Confidence Interval When the Population Standard Deviation Is Known or Large Sample Size · Try It 3

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