A box of folders are to be divided among 17 elementary school classrooms. If each classroom received 31 folders and there were 2 left over, how many folders

Question

I’m really stuck on this question 

Answer 1

every classroom got 31 folders;

multiply by 17 classrooms, to get 527 folders distributed.

add 2 (the # left over), so you know that the box originally had 529 folders in it.