Many of you guessed it correct! As a matter of fact, this riddle is known as the

Monty Hall problem which goes like this

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 No. 1, and the host, who knows what's behind the doors, opens another door, say No. 3, which has a goat. He then says to you, "Do you want to pick door No. 2?" Is it to your advantage to switch your choice? |

This problem was famous for its power to fool people. An experiment was conducted once and 228 people were asked this question, among them many physicists and mathematicians. Only 13% of them chose to switch door, which is the right thing to do.

The simplest way to explained it is this: When you first select a door, you have 1/3 chance to get the correct one and 2/3 to get the wrong one. So, if you do not switch you have a flat possibility to win of 1/3. But what happens if you choose to switch?

If you first select the correct one and you switch afterwards, then you will eventually lose. But if you first choose the wrong one and you switch afterwords, you will eventually win. And because you have 2/3 possibility to select the wrong one, you have more possibilities to win by switching selection!