A woman lives in a skyscraper thirty-six floors high and is served by several elevators which stop at each floor going up and down. Each morning she leaves her apartment and goes to one of the elevators. Whichever one she takes is three times more likely to be going up than down. Why?
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.
John can eat 27 chocolates in an hour, Jacob can eat 2 chocolates in 10 minutes, and Jolly can eat 7 chocolates in 20 minutes. How long will it take them to share and eat a box of 120 chocolates whilst playing Chess?
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