Answer:
2/7
Step-by-step explanation:
You want the fraction of books that are hardback if the ratio of hardback to paperback books is 6:15.
Ratio
We can reduce the ratio to lowest terms by dividing the numbers by their common factor, 3.
6 : 15 = 2 : 5
Fraction
The fraction of books that are hardback is the ratio of hardback books to the total number of books:
hardback : total = hardback : (hardback + paperback) = 2 : (2+5) = 2:7
The fraction of books that are hardback is 2/7.
