The Sunday Times Tetonor Book 2 : 200 Challenging Numerical Logic Puzzles

A mental workout to rival Su Doku! Dozens of compelling and addictive maths puzzles to challenge your mental arithmetic, multiplication skills and powers of deductive reasoning. For all number puzzles addicts. Varying levels of difficulty. Tetonor rules: each number in the main grid can be formed by adding or multiplying a pair of numbers in the strip below the grid. Each pair of numbers should be used twice: once as part of an addition and once as part of a multiplication. For example, a 10 a