Stevie and His Moto

Apr 19, 2010

RAY: Stevie had decided it was time to take his motorcycle to work. It had been in a garage all winter, and, finally, the weather had gotten nice.

So, he gets it out of mothballs, siphons gas out of the lawn mower, fires up the tank, and off he goes. He's enjoying the beautiful sunshine and the warm air. He comes to an intersection that he goes through every day...but he's usually driving his car, and when you're on a motorcycle you're keenly aware of everything around you.

He looks up at a building to his right, and he sees one of those big signs that display the time and temperature. He notices the time, and says, "Geez, I guess I'm really late for work! But, I'll stay late, not to worry!"

Then, the temperature comes up in Fahrenheit, and a few seconds later it comes up in centigrade. Stevie says, "Hah! That's interesting. The digits are exactly reversed." For example, it might have read 31 degrees Fahrenheit, and when it showed the centigrade reading it said "13." He thinks, "I've never seen that before."

The light turns green, and off he goes to work. Well, because he got to work so late, he decided to stay late. When he comes out of work, he realizes he should have checked the weather forecast, because it's drizzly, rainy, and cold.

He's riding home, when he comes to the same intersection. He thinks, "What are the chances I'd ever see that again?" He knows it's a different temperature because it's not warm and sunny like it was when he went to work, and now it's cold, drizzly, and rainy. He sees the temperature in Fahrenheit, and the temperature in centigrade.

TOM: Let me guess! They're the same digits reversed, again.

RAY: What are the chances? Only in a puzzler could this happen! The question is, what was the temperature in the morning when he went to work, and what was the temperature when he went home?
RAY: Here's the answer. Now I don't know if there's an algebraic way to solve this, but I know how I'd solve it. I'd put the two thermometers together. And it turns out that in the morning when the sun was out and it was balmy, it was 28 degrees Celsius which is 82 degrees Fahrenheit.

TOM: Yeah.

RAY: And, of course, assuming that whatever algorithm the thing is using it's rounding off to the closest number. And at night when he came home and it was drizzly and raining and ugly, it was 16 degrees and 61 degrees.

TOM: Wow.

RAY: It only works if the number is between 50 and 99 Fahrenheit because below 50 is ten degrees centigrade. So you can't reverse the digits if it's nine degrees centigrade, there's nothing to reverse. Anyway, who's our winner?

TOM: The winner is Karen German from Franklin, Tennessee, and for having her answer selected at random from all the correct answers that we got, Karen's going to get a $26 gift certificate to the Shameless Commerce Division which is at And with that certificate she can get an official Car Talk baseball hat, since it is baseball season now. We're going to sell Car Talk football helmets next fall!

RAY: Congratulations, Karen!

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