Can you replace the question mark with the correct number?

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.

My friends called me Iron59 because my parents are a chemist and a mathematician. What is my real name?

This puzzle is for Harry Potter fans. Do you know why Tom Riddle is called Lord Voldemort?

A and B have a certain number of chocolates with them. If B gives one chocolate to A, they will have an equal number of chocolates. But if A gives one chocolate to B, then A will be left with half the number of chocolates that B has.

Can you find out the number of chocolates they have right now?

Find The Missing Number In the Sequence.
6 25 64 ? 32 1

Can anyone tell me a word in the English dictionary which has a silent 'z'?

You see a boat filled with people, yet there isn’t a single person on board. How is that possible?

Can you find out who is the kidnapper in below Picture and why, Explain ?

Two girls were born to the same mother, on the same day, at the same time, in the same month and year and yet they're not twins. How can this be ?