Answer:
y/b books
Explanation:
We know that there is a total of y textbooks. These y textbooks came in b boxes, with equal numbers of books in each of these b boxes.
To find how many books are in each box, take the total number of books and divide it by the number of boxes:
y ÷ b = y/b
Thus, there are y/b books in each box.
Hope this helps!