Where is the car?

This puzzle is from real life, taken from a TV show.

There are three doors in front of you. New car waits behind one of them; goat is hidden behind each of the remaining two. You may open one of the doors and get what is behind them. You want the car off course. You choose your door. Moderator (who knows where the car is) than opens one of the remaining doors and shows that there is goat. Now he gives you the opportunity to change your decision.

You are standing in front of two closed doors. Will you change your decision?


It matters whether you change your decision or not.

Imagine there were one hundred doors and moderator would open all but two.


It’s better to change the door.

You win in case you chose wrong door at first (odds 2-in-3).

If you don’t change the door you win only in case you originally picked the correct door (1-in-3).