The rules of killer sudoku are very simple:
- Place each number from 1 - 9 exactly once in each row, column and 3x3 bold-lined box that comprise each grid
- The grid also contains sets of cells inside dashed lines (called 'cages'). Each of these cages contains a number. This is the sum total of the cells inside the cage. Thus a '4' means that the cells in that cage sum to 4. A number cannot be repeated within a cage, so a cage comprised of two cells that must total '4' can only contain 3 and 1 in some order, not 2 and 2, because that would involve repeating a digit.
There are a range of different techniques required to solve killer sudoku, so good luck and happy solving! Every puzzle has a single solution that can be found without guessing - logic will always help you find the solution. Solutions are at the back of the book so you can check if you are right, or if not, find where you went wrong.
All of our books are printed on very high quality paper, making the puzzle experience all the more enjoyable.
For other puzzle books and gift ideas, visit www.puzzle-book.co.uk