One year, at Duke, there were these two guys who 
were taking Chemistry and who did pretty well on 
all of the quizzes and the midterms and labs, 
such that going into the final they had a 
solid A. These two friends were so confident 
going into the final that the weekend before 
finals week (even though the Chemistry final was
on Monday), they decided to go up to Uvirginia 
and party with some friends up there. 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 UV for the 
weekend, and had planned to come back in time to
study, but that they had a flat tire on the way 
back and didn't have a spare and couldn't get 
help for a long time and so were late getting 
back to campus. 

Bonk thought this over and then agreed that they
could make up the final on the following day. The
two 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 then turned the page. 
They were unprepared, however, for what they saw
on the next page. It said: 

(95 points) Which tire?