For each of the following you should decide a) What test would you use? b) Why would you use this test?

1. You wonder if changing the format on a statistics test will change the average mark on the test. You randomly select half the class and give them the standard test. The other half receives the test with the new format. You then compare the marks for each half. In analyzing the data you notice that the group that got the standard test has a normal distribution but the new format has created a bimodal distribution in that half of the class.

2. You wonder which gas station has better service Petro Canada or Shell. Over a 10 day period you ask 30 people to visit the Petro Canada and the Shell station. Each person purchases exactly $10 worth of gas at one station then drives across the road and gets $10 at the other station. You then record the time it takes for each person to be served.

3. You want to see if Rec and Leisure students get summer jobs faster than other university students. You find out from the student placement service that the average university student gets a summer job in 4 weeks with a variance of 3 weeks. The average Rec and Leisure student gets a job in 3.6 weeks with a variance of 4.2 weeks.