Data on the numbers of hospital admissions resulting from motor vehicle crashes are given below for Fridays on the 6th of a month and Fridays on the following 13th of the same month. Assume that the paired sample data is a simple random sample and that the differences have a distribution that is approximately normal. Construct a95% confidence interval estimate of the mean of the population of differences between hospital admissions. Use the confidence interval to test the claim that when the 13th day of a month falls on aFriday, the numbers of hospital admissions from motor vehicle crashes are not affected.

Friday the 6th

2

12

9

10

11

Friday the 13th

14

12

13

15

13

In thisexample, d is the mean value of the differences d for the population of all pairs ofdata, where each individual difference d is defined as the number of hospital admissions on Friday the 6th minus the number of hospital admissions on Friday the 13th. Find the95% confidence interval.

____ < d < ____.

(Round to two decimal places asneeded.)

Based on the confidenceinterval, can one reject the claim that when the 13th day of a month falls on aFriday, the numbers of hospital admissions from motor vehicle crashes are notaffected?

A.

Yes, because the confidence interval does not include zero.

B.

Yes, because the confidence interval includes zero.

C.

No, because the confidence interval includes zero.

D.

No, because the confidence interval does not include zero.