You measure my life in hours
I serve you by expiring
I vanish faster when I am thin
and slower when I am thick
The wind is my energy
What am I?

A rubber ball keeps on bouncing back to 2/3 of the height from which it is dropped. Can you calculate the fraction of its original height that the ball will bounce after it is dropped and it has bounced four times without any hindrance ?

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

When Jack was six years old he hammered a nail into his favourite tree to mark his height. Ten years later at age sixteen, Jack returned to see how much higher the nail was. If the tree grew by five centimetres each year, how much higher would the nail be?

You are confined in a room and given two metal rods. Out of these two rods, one is magnet and the other is the iron rod. They look starkly similar. You don't have any other metal object in the room.

How will you decide which one of those is magnet?

You can take four of the five letters out of this word, but the pronunciation never changes. What is the word?

Can you find a five letter word that is left with only two letters if one is removed?

A chicken farmer has figured out that a hen and a half can lay an egg and a half in a day and a half. How many hens does the farmer need to produce one dozen eggs in six days?

Nine marbles are arranged in the image below. Can you slide two marbles to form a square?

In particular commonwealth games, a female participant won silver and gold medals for a single event.

How can this be possible?