Name a key which is hardest to turn.

Can you arrange four 9's and use at most 2 math symbols, to make the total 100?

Can you think of any three-dimensional shape that comprises of exactly two surfaces?

You have two buckets of 11 liters and 6 litres.
How can you measure exactly 8 litres?

What will be the best approach to finding all the prime numbers less than 75 that leave an odd reminder when we divide them with 5?

They are the five precious gems of an everyday sort and all can be found on a Tennis Court. Who are they?

A wealthy man lives alone in a small cottage. Being partially handicapped he had everything delivered to his cottage. The mailman was delivering a letter one Thursday when he noticed that the front door was ajar. Through the opening he could see the man's body lying in a pool of dried blood. When a police officer arrived he surveyed the scene. On the porch were two bottles of warm milk, Monday's newspaper, a catalog, flyers, and unopened mail. The police officer suspects it was foul play. Who does he suspect and why?

What does this Rebus Picture means ?

James bond was pushed out of an aeroplane without any parachute.
He survived, How come?

You can find some missing letters in the picture. By placing two particular letters in the spaces, you can form a nine lettered word beginning from one of the corners and going clockwise direction to the middle. Can you find out the letters and the word?