A statistics teacher wants to see if there is any difference inthe abilities of students enrolled in statistics today and thoseenrolled five years ago. A sample of final examination scores fromstudents enrolled today and from students enrolled five years agowas taken. You are given the following information. Today FiveYears Ago x̄ 82 88 σ2 112.5 54 n 45 36
The 95% confidence interval for the difference between the twopopulation means is
