Einstein VS Mr. Bean

Einstein & Mr. Bean sitting next to each other on a long flight. Einstein says, "Let's play a game! I will ask you a question, if you don't know the answer, you pay me only $5 and
if I don't know the answer, I will pay you $500.."

Einstein asks the first question, "What's the distance from the Earth to the Moon..?"

Mr. Bean doesn't say a word, reaches his pocket, pulls out a $5.

Now, it's Mr.Bean's turn. He asks Einstein, "What goes up a hill with 3 legs and comes down on 4 legs?"

Einstein searches the net and asks all his smart friends. After an hour he gives Mr.Bean $500..

Einstein going nuts and asks, "Well, so what goes up a hill with 3 legs and comes down with 4 legs?" 

Mr.Bean reaches his pocket and gives Einstein 5$ !!!

Einstein CRIED!!! ;D