In random samples of 25 from each of two normal populations, we found the following statistics:

a. Estimate the difference between the two population means with 95% confidence.

b. Repeat part

(a) increasing the standard deviations to s1  255 and s2  260.

c. Describe what happens when the sample standard deviations get larger.

d. Repeat part

(a) with samples of size 100.

e. Discuss the effects of increasing the sample size.

x2 = 469 s2 = 141 x1 = 524 s1 = 129