A Puzzlement
I am an unabashed puzzle geek. I like puzzles. Oven too. We’ve been sharing puzzles to each other’s delight since high school. Perhaps that’s why we didn’t date much. Actually Oven did date. Hmmmm…. What was my problem?

Where was I? Oh, yeah. This is a terrific old math/logic puzzle and it stumps lots of bright people. If you’ve heard it, keep it to yourself. If you haven’t, have a stab at it.

You’re on Let’s Make a Deal, the game show where Monty Hall gives you chances to win fabulous prizes. Monte brings you up on stage and shows you three closed doors, numbered 1 through 3. The crowd is cheering maniacally.

Monty: Well, [insert your name here], it’s nice to see you here.
[insert your name here]: Thanks, Monty.
Monty: Let’s get right to our challenge, shall we?
The crowd erupts in applause.
Monty: First, the prize. Behind one of these three doors is a fabulous NEW CAR! And I’m not talking about a banged-up nineteen-ninety-something piece of s*** Saturn like Doctor Bean drives, I’m talking about a brand new Ferrari!
The crowd goes completely berserk. Two of them are arrested.
Monty: Now, behind each of the other two doors is a gnarly old goat with tuberculosis. And they’re mean, too!
The crowd laughs uproariously. Several of them wet themselves.
[insert your name here]: How’d you get two old mean tuberculosis-infected goats?
Monty: Never you mind that. We spare no expense for the joke prizes. Now for the sake of this challenge, just to make things clear, you want the Ferrari, not the goats. OK? I don’t want to hear some smart @$$ answer that you’re really a veterinarian and the goats are valuable to you. Got it? The goats are just a joke. They’re likely to just kick you and run away. You want the Ferrari.
[insert your name here]: I’m with you. I don’t want the goats.
Monty: Good. Now here’s how the challenge works. Pay attention. I know which of the three doors has the fabulous new Ferrari, but I’m not going to tell you. I’m going to let you pick one of the doors. But I’m not going to open the door that you pick. What I’m going to do is, after you pick a door, I’m going to open one of the doors that you didn’t pick that I know has a goat behind it, and show you the goat.
[insert your name here]: So I pick one door, and you open a different door and show me a goat. So the door that I picked and one other door are still closed.
Monty: Right! Then, since there are two doors that are still closed, I give you a chance to either stay with the door that you picked, or switch your choice to the other closed door. After that, we open the door you settled on, and you get whatever’s behind it. Got it?
[insert your name here]: Yup.
Monty: OK. Let’s give [insert your name here] a big hand! Pick a door. Remember, I know the door behind which is a new Ferrari!
The crowd erupts yet again.
[insert your name here]: I’ll take door 3.
Monty: OK, let’s open door 1 and show him a goat.
Door 1 opens showing you a goat that coughs and falls to the floor.
Monty: Now you can stay with door 3 or switch to door 2 and you get whatever is behind the door that you choose.

Which choice maximizes your chance of winning the car, and why? Feel free to leave your thoughts as a comment (if you haven't heard this before).

I’ll put up the solution as a comment in about 48 hours. - served up by Doctor Bean @ 12:04 AM