Question

There are

13 books on a shelf.
8 of these books are new.
(a) What is the ratio of used books to new books?
(b) What is the ratio of used books to all books?

Answer 1

a). 5:8

b). 5:13

Explanation:

a) Since 8 are new and there are 13 in total.

You subtract 13-8 which is 5

So now you have 5 used books

They gave you the new book count, which is 8, so it is 5:8

b). You already know the amount of used books: 5 and there are 13 books in all,

so it is 5:13

Answer 2

The ratio of used books to new books is 5:8, since 13-8=5.
The ratio of used books to all books is 5:13, since there are 13 total books and 5 used books.