Perk up your mind and start your day off right with this collection of challenging KenKen puzzles. KenKen can be described simply as sudoku with basic math (addition, subtraction and/or multiplication and division). It's a fun, addictive, clever puzzle that's winning fans the world over. This edition contains 100 KenKen puzzles that use all four mathematic applications along with solving instructions and an introduction by puzzlemaster Will Shortz.