Green Means Go!
RAY: Here's the answer. When the signal changed, the cement truck did beat out the dump truck. And my friend didn't have x-ray vision, but what he noticed was -
TOM: The cement truck wasn't turning.
RAY: Exactly! Even though he couldn't see into the cement truck he knew that there was no cement in it because the drum wasn't turning.
TOM: Whoa. That's good.
RAY: Do we have a winner?
TOM: Yeah. The winner this week is Matthew Patterson from Seattle, Washington, and for having his answer selected at random from the pile of correct answers that we actually got, Matthew's going to get a 26-dollar gift certificate to the Shameless Commerce Division at cartalk.com, with which he can get our brand-new four-CD set, Field Guide to the North American Wacko.
RAY: Congratulations, Matthew!
[ Car Talk Puzzler ]