I am the one who remains awake when you sleep. But I need to rest when you awake. Who Am I?

In the image below, you can see two glasses and two matchsticks.You need to move four matchsticks in such a manner that the crosses come inside the glasses. Note: you cannot move the crossed.

As you can see that fifteen matches have been used to form an arrangement. What you have to do is remove any six of them to make them ten.

If two fifty-foot ropes are suspended from a forty-foot ceiling that is twenty feet apart, how much rope will you be able to steal if you have a knife?

Which letter of the alphabet has the most water?

There is a jar in which there are two types of candies.
20 blueberries and 16 strawberries. You perform the following steps:
1) You take out two candies.
2) If the two candies are of the same flavour, you add a blueberry one otherwise, you add the strawberry one.

You repeat these two steps till there is just one candy remaining in the jar. Which flavoured candy will be left?

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

What can jump higher than a building?

Prove that the below maths equation is true.

8 + 8 = 91

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 ?