I’m tall when I’m young, and I’m short when I’m old. What am I?

How can a man go eight days without sleep?

John was running from 40 thieves. John has got 3 gold boxes which weigh as 4kg, 2kg, and 1kg respectively. A witty man asked John to stay with him for seven days in exchange for 1kg gold per day. John needs to stay there for seven days and also do not want to give the witty man any advance. How can John pay for his seven days stay?

You have two bottles of pills marked with labels A and B. The pills are identical. The doctor has asked you to take one A pill and one B pill daily. You cant take more or less than that.

While taking out the pills one day, you took out one pill from A and by mistake took out two from B. You have no idea which pill is which now.

You cant throw away the expensive pills. What will you do now?

Can you count the number of squares in the given picture?

What number does the below three word/phrase identify and why?
1. Deck
2. Year
3. Singing in the Rain

What brings you down but never up?

How can you write nineteen in a manner that if we take out one, it becomes twenty?

There was a blind beggar living on the footpath of a street. Suddenly one day, the beggar's brother died. What was the relation of the blind beggar with the person who died?

PS: Brother is not the answer.

I am taken from a mine and shut up in a wooden case, from which I am never released, and yet I am used by almost every person. What am I?