Hypothesis test - mean (single small sample) Operating temp.

The mean operating temperature of an aircraft engine during level cruize is supposed to be 190 degrees. An airline tested one particular engine at randomly selected times. The mean temperature on these 25 tests was 193 degrees, with a standard deviation of 3 degrees. Should the pilot worry about th engine running hot? Conduct the appropriate hypothesis test at a significance level of 0.05.

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See the attached file for complete solution. The text here may not be copied exactly as some of the symbols / tables may not print.

Step 1: Set the hypothesis. The claim made will be the alternate hypothesis.
H0: = 190
H1: > 190

Step 2: Set the Level of ...

Solution Summary

This post explains the step-by-step process for conducting five-step hypothesis testing for mean with one sample. The steps are explained with formulas and calculations along with interpretation of the final results. The post will help students learn the hypothesis testing and result interpretation in easy way.

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