I've solved about 15 questions from each book, so they're not unused, but I haven't touched them since. You can solve over 500 questions in total. - Title: Sudoku Test, Beginner/Intermediate Level 314 - Title: Number Place 252 Questions + 32 Questions - Content: Train Your Brain, Straightforward/Intermediate Problems - Included: With helpful hints - Number of pages: 314 pages - Number of pages: 252 pages + 32 pages Thank you for looking.