Question

A strength coach claims that his new regiment will add significant distance to how far his players can hit a baseball. The other coaches decide to test this. They randomly select 33 players to go through his regiment. Before starting, they have each player hit 49 baseballs and record their average distance. The players then go through the strength and conditioning regiment. Afterwards, they again hit 49 baseballs, and record the average distance.

Which of the following would be the most appropriate confidence interval for measuring the average difference in the distance the ball traveled before and after the new regiment?
A. Goodness of Fit interval
B. Two-sample z-interval for proportions
C. Paired t-interval for means
D. Two-sample t-interval for means
E. One-sample z-interval for proportions

Answer 1

C. Paired t-interval for means

Explanation:

The answer to this question is the paired t interval for means. The reason is because both of these events are independent. One of the event starts as the other event gets to it's completion. The population standard deviation is not also not known. This makes the paired t interval for means more suitable