Two well-known aviation training schools are being compared using random samples of their graduates. It is found that 70 of 140 graduates of Fly-More Academy passed their FAA exams on the first try, compared with 104 of 260 graduates of Blue Yonder Institute. To compare the two proportions, the assumption of normality of the test statistic is:
A)justified, but it is a borderline case.
B)clearly justified.
C)clearly not justified.

Question

Quizplus · Accepted Answer

The assumption of normality of the test statistic is clearly justified because the sample sizes for both Fly-More Academy and Blue Yonder Institute are greater than 30, which satisfies the criteria for the normal approximation of the binomial distribution. Therefore, we can use a z-test to compare the two proportions.

Two Well-Known Aviation Training Schools Are Being Compared Using Random