The quality control manager of a major cell phone provider is concerned about the life of the cell phone batteries they use. He took a sample of 13 batteries from a recent shipment and used them continuously until they failed to work. The manager measured the number of hours the batteries lasted and found the mean to be 550.4 with a standard deviation of 315.3.
-How would you define the rejection region for this test at ? = .10?

Question

The quality control manager of a major cell phone provider is concerned about the life of the cell phone batteries they use. He took a sample of 13 batteries from a recent shipment and used them continuously until they failed to work. The manager measured the number of hours the batteries lasted and found the mean to be 550.4 with a standard deviation of 315.3.
-How would you define the rejection region for this test at ? = .10?
A)t > 1.711
B)t > 1.356
C)t > 2.492
D)t > 3.646 and t < -3.646
E)t > 3.787

Quizplus · Accepted Answer

The rejection region for a one-tailed t-test at a significance level of 0.10 with 12 degrees of freedom (n-1 = 13-1) is t > 1.356.

The Quality Control Manager of a Major Cell Phone Provider