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OpenStax, Introductory Statistics 2e §10.2 Two Population Means with Known Standard Deviations · Try It 1 · Statistics · Hypothesis testing

Two Population Means with Known Standard Deviations · Try It 1

The means of the number of revolutions per minute of two competing engines are to be compared. Thirty engines of each type are randomly assigned to be tested. Both populations have normal distributions. shows the result. Do the data indicate that Engine 2 has higher RPM than Engine 1? Test at a 5% level of significance.

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OpenStax, Introductory Statistics 2e · §10.2 Two Population Means with Known Standard Deviations · Try It 1

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