The host of a game show, offers the guest a choice of three doors. Behind one is a expensive car, but behind the other two are goats.
After you have chosen one door, he reveals one of the other two doors behind which is a goat (he wouldn't reveal a car).

Now he gives you the chance to switch to the other unrevealed door or stay at your initial choice. You will then get what is behind that door.

You cannot hear the goats from behind the doors, or in any way know which door has the prize.

Should you stay, or switch, or doesn't it matter?

In Greek mythology, the Sphinx sat outside of Thebes and asked this riddle of all travellers who passed by. If the traveller failed to solve the riddle, then the Sphinx killed him/her. And if the traveller answered the riddle correctly, then the Sphinx would destroy herself. The riddle:

What goes on four legs in the morning, on two legs at noon, and on three legs in the evening?

Oedipus solved the riddle, and the Sphinx destroyed herself.

What is in seasons, seconds, centuries and minutes but not in decades, years or days?

Take 9 from 6, 10 from 9, 50 from 40, and leave 6.

How Come ??

You knock a Table over in the library, and suddenly 20 eyes are looking at you.

A bomb goes off.
Carnage.
One person, only a few feet away, survives! How can this be?

Which letter of the alphabet has the most water?

How can you make a TV, a bed, a dog, and a car liquid?

A man was driving a black truck. His lights were not on. The moon was not out. A lady was crossing the street. How did the man see her?

I speak without a mouth, and hear without ears. I have no-body, but I come alive with the wind. What am I?