##### Feb 28, 1998

**RAY: ** The new puzzler.

**TOM:** Oh, you have one?

**RAY:** I do have one.

**TOM:** I can hardly wait.

**RAY:** Well, I have a Crusty puzzler which I will save until next week.

**TOM:** I can hardly wait. What is it?

**RAY:** Well, this was sent to us from cyberspace by Roy Richarde.

**TOM:** Good. Read it.

**RAY:** It says --

**TOM:** Hurry up.

**RAY:** While driving around Luxembourg, on a recent trip to Europe, I caught a glimpse of a billboard that immediately brought Car Talk to mind.

**TOM:** Yeah.

**RAY:** The billboard was brightly colored with a cartoon like a pig on the bottom, but it wasn't just a pig that brought Car Talk to mind. Across the center of the sign was written an equation. Write this down.

**TOM:** I'm going to write it down. Go ahead.

**RAY:** D.

**TOM:** D. Small or big.

**RAY:** Yeah.

**TOM:** D equals --

**RAY:** Equals V over 10.

**TOM:** Yeah.

**RAY:** In parentheses. Squared. That quantity squared. The whole thing divided by two. OK? You got it. So, the quantity --

**TOM:** Whoa!

**RAY:** V over 10.

**TOM:** Yeah. Square.

**RAY:** Squared. Divide V by 10, square it. You divide that whole thing by 2. Got it?

**TOM:** I've got it. Yeah.

**RAY:** Right? You got it?

**TOM:** Yeah. And this was a billboard?

**RAY:** This was a billboard. He says, remembering a discussion on the show of several months ago, I immediately knew what this was all about.

**TOM:** Wow!

**RAY:** What was it?

**TOM:** That's it? That's the question? No, oh, you gave a hint. Remembering a discussion on our show.

**RAY:** Remembering a discussion on Car Talk of a few months ago.

**TOM:** I knew immediately what this meant.

**RAY:** And all the hints are there. I mean Luxembourg. I mean you name it. You name it. It's all there, man.

**TOM:** Richarde.

**RAY:** Roy Richarde. Luxembourg. Europe.

**TOM:** Yeah.

**RAY:** D. D is there.

**TOM:** V. V is there too.

**RAY:** D and V. They're both there.

**TOM:** All right.

**TOM:** First of all, I am struck by the fact that any country would think that there were enough people driving around who would even know that it was an equation about anything.

**RAY:** Well, you know I was reading an article in the paper recently about how poorly American kids scored in science and math tests.

**TOM:** Yeah.

**RAY:** They were like 97th out of 91 of all the nations tested, and all the European nations typically do much better. I looked for France and they were unfortunately right up there, but Europeans in general, I guess, were a lot more literate in mathematics than we Americans are.

**TOM:** I guess so.

**RAY:** And what this equation means is that the distance that you should trail another car on the highway is determined by taking your velocity in kilometers per hour.

**TOM:** Yeah.

**RAY:** Let's say it's a 100.

**TOM:** Say it's a 100 kilometers per hour.

**RAY:** Which is 60 miles an hour in our lingo.

**TOM:** Yeah.

**RAY:** Divided by 10.

**TOM:** OK. So, that gives me 10.

**RAY:** Square that.

**TOM:** Square that. There's two. There's a 100.

**RAY:** Divide that by two.

**TOM:** There's 50.

**RAY:** Yeah. So, of course, the units are all wrong, but that's all right.

**TOM:** That's all right, but it means if I were driving at a 100 kilometers per hour, which is 60 miles per hour, I should be 50 meters or 150 feet --

**RAY:** Roughly.

**TOM:** Roughly behind the car in front of me.

**RAY:** There you go. Cute, huh?

**TOM:** Wow!

**RAY:** All right. What's the equation? Do you remember it?

**TOM:** D equals V over 10 squared, all over two.

**RAY:** Of course, while most people were trying to do the math, they'd crash into another car. And who's our winner anyway? We have a fabulous prize and who got it, Tommy?

**TOM:** The winner is from Luxembourg, someone named Diane Swan, from Eeston. E-E-S-T-O-N. Not eastern, but East-ton, Maryland.