All New Puzzle Book (Mensa)
More than 500 Mensa derived enigmas, conundrums and puzzles.
Four titles from the testers of Mensa, the global high IQ society. Puzzling and other forms of brain exercise are extremely good for you, so here are hundreds of riddles, Sudoku, number problems, logic puzzles and more, complete with solutions and explanations, as well as full IQ tests to identify and improve specific aspects of your problem-solving abilities. For anyone from casual puzzlers looking for something a little more challenging, to experienced solvers really looking to stretch themselves.