A Perfect Square
RAY: Well, our number ends with the number two. And there are no perfect squares that end in or have a units digit of two. It's impossible.
TOM: Impossible indeed.
RAY: Why? Because the units digit of any perfect square is determined by the units digit of its square root. Take the number one, for example, square it and you get one. Take the number two and square it, it comes out four. The number three comes out nine. But there is no number that you can square and get a two at the end. That's what Crusty knew. Do we have a winner?
TOM: The winner this week is Diana Carzoli from West Des Moines, Iowa, and for having her answer selected at random from among the pile of correct answers that we got, Diana is going to get a 26-dollar gift certificate to the Shameless Commerce Division at cartalk.com with which she can get one of our CD collections like, The Best and Second Best of Car Talk.
TOM: Congratulations to you, Diana baby!
[ Car Talk Puzzler ]