A boy purchased a book from a bookkeeper and gave him $100.
The cost of the book is $50 but the bookkeeper has no change, so he gets the change from the next shop and returns the boy his $50.
After some time the next shopkeeper came with the $100 note and told the bookkeeper that the note was a fraud, so he took the money back.
You have a square. What you have to do is cut and reassemble the square such that you create a Red Cross sign that has the same volume as that of the square.
In 2007, a puzzle was released and $2 million prizes were offered for the first complete solution. The competition ended at noon on 31 December 2010, with no solution being found. Wiki