QUESTION 11

You may need to use the appropriate appendix table or technology to answer this question.

The following information is given concerning the ACT scores of high school seniors from two local schools.

School A	School B
n1 = 13	n2 = 13
x1 = 24	x2 = 22
12 = 16	22 = 11

Develop a 98% confidence interval estimate for the difference between the two population means. Assume the two populations are normally distributed. (Use School A School B. Round your answers to three decimal places.)

to

QUESTION 13

The following information was obtained from independent random samples taken of two populations.

	Sample 1	Sample 2
Sample Mean	47	42
Sample Variance	75	136
Sample Size	10	16

Find the degrees of freedom for the t distribution.

11

23

26

28