A Marine drill instructor recorded the time in which each of 10 recruits completed an obstacle course both before and after basic training. To test whether any improvement occurred, the instructor would use a t-distribution with 9 degrees of freedom.

Question

Quizplus · Accepted Answer

Since the sample size is less than 30 and the population standard deviation is unknown, a t-distribution should be used and the degrees of freedom would be n-1, making it 9 in this case.

A Marine Drill Instructor Recorded the Time in Which Each