A WWI Biplane and a Jackass (The Four-Legged Kind!)

Sep 21, 2009

RAY: This is from my back-to-school series.

On Tommy's most recent departure from his senses, he bought himself a WW1 vintage biplane, the kind he flew when he was a boy. His purpose was to fly this plane from One Horse, Nevada, to the nearest town, distance and name unknown.

Now this paragon of aeronautical engineering can fly twenty times faster than Tommy can walk. So he takes off and starts flying. When he reaches the halfway point, he lands the plane. And, get this, he sees a guy walking with a jackass.

Tommy says, 'You can have the plane, give me the jackass.' Even though the jackass can travel only half as fast as Tommy can walk, Tommy completes the journey on the jackass, with his fine Italian loafers never touching the ground.

Here's the question: If Tommy had traveled the whole distance on foot, no plane, no jackass, would this odyssey from One Horse have taken less time, more time or the same amount of time?

RAY: Here's the answer. If Tommy had traveled the whole distance on foot, no plane, no jackass, this odyssey from One Horse would have taken him less time.

TOM: Get out.

RAY: And here's why. The trip on the jackass used up exactly the same amount of time that the whole trip would have taken on foot, because the jackass goes only half as fast as Tommy can walk. So the jackass used up X amount of time, and walking would have used up the same amount of time. So the plane trip had to have made the trip longer by the duration of the plane trip. The trip would have been absolutely shorter if he had walked the whole way. But with only one jackass and no plane, it wouldn't have been anywhere near as interesting. So who's our winner?

TOM: Our winner this week is Bob Long from Orlando, Florida, and for having his answer selected at random from among all the correct answers that we got, Bob's going to get a $26 gift certificate to the Shameless Commerce Division at cartalk.com, with which he can get our brand-new multicolor Car Talk reusable shopping bag.

RAY: Yeah, this is a grocery bag with Car Talk designs on it, right?

TOM: Yeah, and it's reusable.

RAY: Yeah, after my brother uses it for groceries he can put it over his head and go out on a date.

TOM: Like I said, it's reusable. Congratulations, Bob!

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