Here are over 300 tantalizing puzzles, brain-teasers and riddles by one of the greats mathematical geniuses of the twentieth century, Shakuntala Devi, popularly known as the 'human computer'. The puzzles include every possible type of mathematical recreation; time and distance problem as and money riddles, puzzles involving geometry and elementary algebra, and just plain straight thinking. Often entertaining, but always stimulating, the puzzles included in the book offer hours of fun and relaxation.