An educational researcher is studying two similar high schools in different states. Suppose that 50% of all 425 students at high school A have taken a college-level course, while 40% of all 525 students from high school B
have taken such a course. The researcher plans on taking separate random samples of 50 students from each
high school to look at the difference (A - B) between the proportions of students who have taken a college-
level course in each sample.