A weekly feature of SideSpin.

Suppose you're on a game show, and you're given the choice of three doors. Behind one door is a car, behind the others, goats. You pick a door, say #1, and the host, who knows what's behind the doors, opens another door, say #3, which has a goat. He says to you, "Do you want to pick door #2?" Is it to your advantage to switch your choice of doors?

—Craig F. Whitaker

Yes, there is a huge advantage to switching your choice of doors. For starters, he just handed you a goat for Christ’s sake. Do you know how great it would be to own a goat? You’d never have to mow your lawn again (I think they eat grass). And they grow wool or some sort of cloth, so basically you’re getting free t-shirts for life. Also, what the host didn’t tell you is that the goat ate the keys to the car, so if you want the car you really need to pick the goat.

A shopkeeper says she has two new baby beagles to show you, but she doesn't know whether they're male, female, or a pair. You tell her that you want only a male, and she telephones the fellow who's giving them a bath. "Is at least one a male?" she asks him. "Yes!" she informs you with a smile. What is the probability that the other one is a male?