In a hypothesis test that a population mean is at least 50, it is a Type I error to conclude that the mean is
A) at least 50 when it is not.
B) at least 50 when it is.
C) less than 50 when it is not.
D) less than 50 when it is.

Question

Quizplus · Accepted Answer

A Type I error occurs when the null hypothesis is rejected when it is actually true. In this context, if the null hypothesis is that the population mean is at least 50, then rejecting it to conclude the mean is less than 50 when in fact it is at least 50 constitutes a Type I error.

In a Hypothesis Test That a Population Mean Is at Least