Challenging Brainteasers - Mensa Author:Bernardo Recaman Santos Puzzle these out! Math and logic become more fun than ever when they're turned into brainteasing games. Some of these puzzles use cards or marbles; others have diagrams, grids, and lively illustrations; still more present their questions as a story or riddle. Here are just two examples: Look at this sentence: Dale is wrong. Using all thes... more »e letters, can you spell a single word? Or try Non-aligned Pawns: How must the 8 white and 8 black pawns in a chess set be placed on a board so that no three pawns end up in the same horizontal, vertical, or diagonal line? They'll really test your smarts!« less