survey reported that in a sample of 300 students who attend two-year colleges,
105 work at least 20 hours a week.
In a sample of 225 students attending private universities, only 20 students work at least 20 hours per week.
Use this data to find the 95% confidence interval for p1 – p2, the true difference in the proportion of students
in two-year colleges and the proportion of students in private universities who work at least 20 hours per week.