The Flat Tire

An Urban Legend

As told by Jill Silos...

A story frequently heard around the dorm rooms and coffee houses where college students hang out, detailing an action generally attributed to a famous Dartmouth professor (who is so famous I can't remember his name right now):

Two students decide to go skiing for the weekend, and are having such a good time they decide to blow off the (calculus, I believe) exam that they have scheduled for Monday morning in order to get some final runs in before they head back to school.

They decide to tell the prof that they got a flat tire and therefore deserve to take the exam at a rescheduled time.

Hearing the story, said professor agrees that it really was just bad luck, and of course they can take the exam later. At the appointed time, the prof greets them and places them in two separate rooms to take the exam.

The few questions on the first page are worth a minor 10% of the overall grade, and are quite easy. Each student grows progressively confident as they take the test, sure that they have gotten away with fooling the professor. However, when they turn to the second page they discover that they really haven't.

The only question on the page, worth 90% of the exam, reads: "Which tire?"

Email example contributed by Kristin R., Apr. 26, 1999:

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 Virginia 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 morality 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?

Analysis: You may have noticed that each of the two versions of the incident recounted above is said to have occurred at a different school: Dartmouth University in the first case, Duke in the second. Other colleges (and high schools) have been named as well over time. This is partly a function of how old the story is — 40 years old, at least — and partly due to the propensity of storytellers everywhere to localize a tale for maximum impact.

The Duke University version is widely held to be true, having been confirmed on more than one occasion by Duke chemistry professor James F. Bonk himself. A fixture at Duke since 1959, Professor Bonk has long been beloved by faculty and students alike for his absolute command of the subject, his dry wit, and the legendary, two-word exam question quoted above.

"It's a true story that to my knowledge is based on a real incident, but is tremendously embellished," he explained to a writer for the Duke Chronicle in 2001. "My own recollection is not terribly clear because if I'm in the right ballpark, it's something that happened way back in the '60s. It is a great story and certainly I wasn't going to do anything to destroy a great story."

It is likely nonetheless that variants of the story were already in circulation before Professor Bonk enacted it in real life. Consider this example from a humor column published in the Port Arthur (Texas) News on September 1, 1966:

It was a bright spring day and four boys failed to show up at high school until noon, reporting they'd had a flat tire.

The teacher smiled understandingly and informed the youths that they'd missed a morning test so she would give them another. She requested that they sit apart from one another. The exam proved very brief.

As the boys sat, pencils in hand, the teacher gave them one question: "Which tire was flat?"

Whether the Duke University incident happened earlier and provided the inspiration for the 1966 variant, or whether Professor Bonk heard an already-existing version of the story and consciously or unconsciously acted it out in his classroom (see ), we have no way of knowing. We can accept it as true in either case.

Sources and further reading:

Bonk: In His Element
Duke Alumni Magazine, July-August 2001

Duke Chronicle, April 25, 2001

"Supper Table Talk"
Port Arthur News, Sept. 1, 1966

Updated 11/18/09