Sudoku puzzles are not only fun and addictive, they also work to maintain good mental fitness, building logic and boosting problem .

With smaller grids that can be completed in half the time, you'll get the satisfying buzz of completing a puzzle when you only . For instance, if you have to make 17 from two squares in a killer sudoku, then you know straight away these contain the 9 and the 8 so they can be written in as pencilmarks and removed as options from all the other squares in the grid.

The first is to learn the combinations of numbers that have the least options: there are tables available on the internet that contain the various different ways that certain numbers can sum together and these are very useful. KEEPS YOUR MIND HEALTHY: Sudoku puzzles are a proven method for keeping the mind healthy and combating Alzheimer's and Dementia. We have Very Easy, Easy, Standard, Hard, Very Hard, Extreme levels for beginners and experienced Sudoku Puzzlers. This addition to the successful Times Killer Su Doku series will test your skills to the limit, adding the challenge of arithmetic and taking Su Doku to a new and even deadlier level of difficulty.

It's time to find out with this fun quiz that contains 20 questions about the life and times of William Shakespeare.

But wait a minute - if the value were only lower than 5, say it was 4, then the final square would have to contain 10 to complete the sum to 45. Please include what you were doing when this page came up and the Cloudflare Ray ID found at the bottom of this page. Our passion is to publish books that entertain, enlighten and are ultimately thoroughly enjoyed, by individuals, families or amongst friends.