Respuesta :

Answer:

16

Step-by-step explanation:

the 9 parts of the ratio is equivalent to 72 books

divide number of books by 9 to find one part of the ratio

[tex]\frac{72}{9}[/tex] = 8 ← 1 part of the ratio

2 parts = 2 × 8 = 16 ← number of bookmarks sold