100 prisoners are stuck in the prison in solitary cells. The warden of the prison got bored one day and offered them a challenge. He will put one prisoner per day, selected at random (a prisoner can be selected more than once), into a special room with a light bulb and a switch which controls the bulb. No other prisoners can see or control the light bulb. The prisoner in the special room can either turn on the bulb, turn off the bulb or do nothing. On any day, the prisoners can stop this process and say "Every prisoner has been in the special room at least once". If that happens to be true, all the prisoners will be set free. If it is false, then all the prisoners will be executed. The prisoners are given some time to discuss and figure out a solution. How do they ensure they all go free?

What seven-letter word has hundreds of letters in it?

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

If you say my name, I will no longer exist. What am I?

A Child was born in Lahore, Pakistan. Still, the child is not a Pakistani citizen. why?

When I got four, I have it none.
When I got two, I have it some.
When I got none, I have it all.

What is it?

A little girl goes to the store and buys one dozen eggs. As she is going home, all but three break. How many eggs are left unbroken?

Take 9 from 6, 10 from 9, 50 from 40, and leave 6.

How Come ??

In the picture that is attached with this question, you can find a square which comprises of four little squares inside it. Consider this square to be made with matchsticks. You have to remove two matchsticks such that only two squares remain instead of five.How will you do it ?

A father's child, a mother's child, yet no one's son.

Who am I?