One year there were these 2 guys who were taking Chemistry and who did pretty well on all of the quizzes and the midterms and the labs, etc... such that going into the final they had a solid A. These two friends were so confident that the weekend before finals week (even though the Chemistry final was on Monday), they decided to go up to University of Virginia and party with some friends.
So they did this and had a great time. However, with their hangovers and everything, they overslept all day Sunday and didn't make it back to Duke until early Monday morning. Rather than taking the final then, what they did was to find Professor Bonk after the final and explain to him why they missed the final. They told him that they went up to U of VA for the weekend and had planned on returning in time to study, but that they had a flat tire on the way back and no spare. They couldn't get help for a long time and so they were late in getting back to campus.
Bonk thought this over and then agreed that they could make up the final on the following day. The 2 guys were elated and relieved.
So they studied that night and went in the next day at the time that Bonk had told them. He placed them in separate rooms and handed each of them a test booklet and told them to begin. They looked at the first problem, which was something simple about molarity and solutions and was worth 5 points. "Cool," they thought. "This is going to be easy." They did that problem and turned to the next page. They were unprepared, however, for what they saw on the next page. It said:
(95 points) Which tire?