It can't be seen, can't be felt, can't be heard, and can't be smelt.
It lies behind stars and under hills, And empty holes it fills.
It comes first and follows after, Ends life, and kills laughter.
What is it?

Transform the word THINK into BRAIN while changing only one letter at a time in a manner that each of the word in the process is a real word!!!

What has lots of eyes, but can’t see?

Can you count the number of squares in the figure below?

Jigsaw captured 100 people and make them stand in a circle and all these people are labelled as Person1, Person2, Person3... Person100. He made them play a crazy game in which Person 1 shot Person 2 and pass the gun to the next person and so on until one stands alive.

Which person will survive in the end?

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 ?

What four weights can be used to balance from 1 to 30 pounds?

As easy as you can get into me, it is as hard to get out of me.

Do you know what I am?

Can you count the number of triangles in the picture below?

Which is the smallest number that you can write using all the vowels exactly once?