There's no better way to have fun and give your brain a workout than by picking up a pen and taking on a new challenge: and this book provides lots of them. With a huge range of different number puzzles, from sudoku and kriss kross to brain chains and kakuro, there are over 150 ways for you to test your mental agility and buff up your number skills . and if you get stuck, the answers are all given in the back. Perfect for everyone who relishes a varied challenge, whether they have a 10-minute break or an afternoon of leisure!.