Question

A coach uses a new technique in training middle distance runners. The times for 9 different athletes to run 800 meters before and after this training are shown below.

Athlete	A	B	C	D	E	F	G	H	I
Time before training	115.2	120.9	108.0	112.4	107.5	119.1	121.3	110.8	122.3
Time after training	116.0	119.1	105.1	111.9	109.1	115.2	118.5	110.7	120.9

a. Construct a 99% confidence interval for the mean difference in time before and after training.

<differenceintime<   Keep your values in 2 decimal places.

b. What can youconclude from the confidence interval? Hint:Is trainging effective? Why?

  

Answer 1