Independent random samples were selected from two binomial populations. The sizes and number of observed successes for each sample are shown in the following table.
Sample 1 Sample 2
n1 = 200..................... n2 = 200
n1 = 110..................... x2 = 130
a. Test H0: (p1 - p2) = 0 against Ha: (p1 - p2) < 0. Use α = .10.
b. Form a 95% confidence interval for (p1 - p2).
c. What sample sizes would be required if we wish to use a 95% confidence interval of width .01 to estimate (p1 - p2)?