Sudoku Book Large Print for Ages 8-80 Improve Logical Thinking and Deductive Reasoning Skills8 1/2 " x 11 " Book formatOne Large Print Puzzle per page Large Print Answer Key on the back of each page200+ pagesThese are extremely difficult puzzles designed for someone who is beyond good at Sudoku and/or Samurai SudokuEach 9x9 puzzle is a stand-alone Sudoku grid but they have been combined to form a killer interlinked 5 grid master puzzle!Hours of fun logical and deductive reasoning in every volume.If this was easy, wait for the next oneThe difficulty level increases with volume numbersGreat for smart kids, teens, adults, and seniorsMakes a great gift for any birthday or holidayEntertainment that exercises the brain with no screens--- Name a better present!