The Monty Hall Problem
The Monty Hall Problem, named after the host of the long-running game show "Let’s Make a Deal," is a statistical puzzle that seems counterintuitive.
A recurring deal on the show featured contestants choosing one of three closed doors, with a big prize behind one of them and something else, like a goat, behind each of the others.
If you always switch doors after Monty Hall reveals a goat, then your odds of winning are two-in-three, or 66.7 percent on average. If you keep your original choice, your chances of winning are just one-in-three, or 33 percent on average.
That seems weird, because after Monty reveals a goat, there are two closed doors left, and it might seem as if there should be a 50-50 chance that the car is behind either door.
Play it and see.
Via NYTimes