Question

0n Monday the school library started the day with 12,765 books. During the day students checked out 398 books, and a certain number of books were returned. If the library ended the day with 12,479 books, how many books were returned?

Answer 1

Lets start with the basics. 12,765 books are in total. We need to take 398 from that. 12765 - 398 = 12367. That means x people returned the book to reach 12,479. 12,479 - 12367 = x. X = 112.

112