Xuri Primary School distributed 547 books to six grades. Why is there always a grade with at least 92 books? Why?
Because of 547 books, six grades can't share them equally. If 547 books are divided into six grades on average, one grade is 9 1.2, which is not an integer, so it cannot be divided equally. There are 92 books in one grade and 9 1 book in the other five grades, which is exactly 547 books. Therefore, Sunrise Primary School distributed 547 books to six grades, one grade, and got at least 92 books.