Understanding Basic Statistics 6th Edition by Charles Henry Brase,Corrinne Pellillo Brase

Exercise 20

Basic Computation: Confidence Interval for p 1 p 2 Consider two independent binomial experiments. In the first one, 40 trials had 15 successes. In the second one, 60 trials had 6 successes.
(a) Check Requirements Is it appropriate to use a normal distribution to approximate the
distribution Explain.
(b) Find a 95% confidence interval for p 1 p 2.
(c) Interpretation Based on the confidence interval you computed, can you be 95% confident that p 1 is more than p 2 Explain.