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?

What is 3/7 chicken, 2/3 cat and 2/4 goat?

You see a boat filled with people, yet there isn’t a single person on board. How is that possible?

Below, you will find the mathematical proof that 10 equals 9.99999?. But is that possible or there is something wrong about it? Can you find the error?

x = 9.999999...
10x = 99.999999...
10x - x = 90
9x = 90
x = 10

Find the next number in the series.
1 10 24 43 67 ?

You can see it everyday, But cannot touch it at will. What is it?

You have two strings whose only known property is that when you light one end of either string it takes exactly one hour to burn. The rate at which the strings will burn is completely random and each string is different.

How do you measure 45 minutes?

How can you tell a raw egg from a hard-boiled egg?

It has horns but can’t beep. It is like to bleat but It is not a sheep. What is it?

If eleven plus two equals one, what does nine plus five equal?