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OpenStax, Introductory Statistics 2e §9.5 Additional Information and Full Hypothesis Test Examples · Try It 5 · Statistics · Hypothesis testing

Additional Information and Full Hypothesis Test Examples · Try It 5

A company records the mean time of employees working in a day. The mean comes out to be 475 minutes, with a standard deviation of 45 minutes. A manager recorded times of 20 employees. The times of working were (frequencies are in parentheses) 460(3); 465(2); 470(3); 475(1); 480(6); 485(3); 490(2).
Conduct a hypothesis test using a 2.5% level of significance to determine if the mean time is more than 475.

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OpenStax, Introductory Statistics 2e · §9.5 Additional Information and Full Hypothesis Test Examples · Try It 5

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