A man has eighty-one cows ( numbered 1,2,3...81 as such). The beauty is that cow no. 1 gives 1ltr of milk, cow no. 2 gives 2ltrs of milk and so on. The man wants to equally distribute the cows among his nine sons so that each one of them gets the same quantity of milk.

I inserted a coin in a bottle and closed its mouth with the help of a cork. Now, I was able to take the coin out from the bottle without taking out the cork or breaking the bottle. Can you tell me how I did it?

I am the beginning of everything, the end of everywhere. I'm the beginning of eternity, the end of time and space. What am I?

If I remove one from eleven it becomes Ten and if I remove one from nine also becomes Ten. How?

What question can you never answer yes to?

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

How can you make number one disappear by adding something to it?

It is always ahead of me yet I can never see it. What is it?

If we tell you that there is a relation between the numbers and letters in the given figure, can you analyze it and find the missing letter in the last box?

I had an infinite supply of water and 5 litres and 3 litres jars.

How would you measure exactly 4 litres in the least number of steps?