A certain street contains 100 buildings. They are numbered from 1 to 100. How many 9's are used in these numbers?

The host of a game show offers the guest a choice of three doors. Behind one is an 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?

I am the beginning of everything, the end of everywhere. I'm the beginning of eternity, the end of time and space. What am I?

Replace the question mark with the correct number in below Picture:

Can you name some countries which do not have the alphabet 'A' in them?

How many sides does a circle have?

You need to move three matchsticks to form three squares. Can you do it?

What month of the year has 28 days?

John replied, when asked how old he was. In 2 years he will be twice as old as he was five years ago.' How old is he ?

Why is Saturday stronger than Monday?