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OpenStax, Introductory Statistics 2e §8.1 A Single Population Mean using the Normal Distribution · Exercise 12 · Statistics · Normal distribution

A Single Population Mean using the Normal Distribution · Exercise 12

The U.S. Census Bureau conducts a study to determine the time needed to complete the short form. The Bureau surveys 200 people. The sample mean is 8.2 minutes. There is a known standard deviation of 2.2 minutes. The population distribution is assumed to be normal.

Suppose the Census needed to be 98% confident of the population mean length of time. Would the Census have to survey more people? Why or why not?

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OpenStax, Introductory Statistics 2e · §8.1 A Single Population Mean using the Normal Distribution · Exercise 12

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