TURING TESTS EXPERT NUMBER CRUNCH PUZZLES

Follow in the footsteps of famous World War II codebreaker Alan Turing, who used impeccable logic to decipher the military codes used by Germany and its allies. These expert puzzles offer a tough but enjoyable mental work-out, with puzzles in three levels of difficulty. Starting at the top with the number provided, your challenge is to work downwards from one box to another, applying the instructions to your running total until you reach a final answer. Sales support the work of The Turing Trust, which provides computers to schools in Africa.