Quickest way I've seen to understand this result is referenced on Wikipedia: An intuitive explanation is that if the contestant picks a goat (2 of 3 doors) the

Quickest way I've seen to understand this result is referenced on Wikipedia: An intuitive explanation is that if the contestant picks a goat (2 of 3 doors) the contestant will win the car by switching as the other goat can no longer be picked, while if the contestant picks the car (1 of 3 doors) the contestant will not win the car by switching. The fact that the host subsequently reveals a goat in one of the unchosen doors changes nothing about the initial probability. http://en.wikipedia.org/wiki/Monty_Hall_problem http://en.wikipedia.org/wiki/Monty_Hall_problem