Set of math problem collection and answer key. - Title: Systematic Problem Collection Math 1 - Type: Problem Collection - Volume: 1 - Included: Answer Key - Condition: There are some pencil markings on the problems, but none on the answer key, including the name section. There are some tears, but it doesn't interfere with reading the content. The answer key was only used for half a year, so it's in relatively good condition with some minor scratches. I plan to cut out the name section, but please let me know if you prefer it to be blacked out with a marker. I also have other items related to Systematic Math 1 for sale. If you wish to purchase multiple items, I will discount the shipping cost. I previously had the Geometry edition for sale, but it has already been purchased. Just in case.