Refer to Exercise 3.

Find the critical value for a 95% confidence interval for the difference p1 − p2.

Exercise 3

In a survey of 300 randomly selected female and 240 male holiday shoppers, 87 of the females and 98 of the males stated that they will wait until the last week before Christmas to finish buying gifts. Let p1 be the population proportion of males who will wait until the last week and let p2 be the population proportion of females. Compute a point estimate for the difference p1 − p2.