250 excellent puzzles at the level of silver. All riddles have only 1 solution. 2 puzzles per page. Enough space for your thoughts and decisions. Very convenient and practical. Good brain support in shape. Expands creative thinking. Wide inner edges allow recording of solution options. Ideal gift for all fans of puzzles. Sudoku 10x10, separated by smaller rectangles of 5x2 cells. It is necessary to fill empty cells with numbers from 1 to 10, each of the digits should appear only once in each line of the 10x10 square, 10x10 column and 5x2 rectangle. No matter what figure of the playing field we take in all the cells around it (horizontally, vertically or diagonally), there should not be such a figure. This means that for any randomly taken 3x3 square, the central figure of this square occurs only once in it. Excellent purchase for fans of Sudoku. A great book for relaxing in your spare time. There are 148 pages. The format is 6 '' x 9 ''. I hope you enjoy my book. I would also be very grateful if you could write a review. Thank you. Best regards, Andrii Pitenko