Books are typically printed so one sheet holds four pages. That’s two on the front and two on the back. For example, in a regular book, pages 1 and 2 are on the front of a sheet, and 3 and 4 are on the back.
This is super important because when you rip out one sheet, you’re not just taking two pages. You’re yanking out four pages total, two from the front and two from the back.
Let’s look at figuring out how many pages are torn when specific pages like 7 and 8, 100 and 101, and 222 and 223 are gone.
Pages 7 and 8 are on the same side of a sheet. Since pages print in pairs, that means 5 and 6 are on the back. So, ripping out the sheet with 7 and 8 also takes out 5 and 6. In total, four pages go: 5, 6, 7, and 8.
Pages 100 and 101 are part of the same sheet too. The page order keeps going, so 99 and 102 are on the opposite sides. Tear out this sheet, and you’re losing four pages: 99, 100, 101, and 102.
