A fun hobby that exercises your brain and gives you a sense of accomplishment. That's the perfect description of the numbers puzzle from Japan called sudoku.
* Sudoku 9x9 - 240 Extreme sudoku puzzles with solutions:
* Suitable for all ages.
* Can record the time it takes to play each game.
* This great book contains 240 fun and extrame Sudoku puzzles
* With all the solutions at the rear of the book in case you get stuck
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