Answer:
11 shelves are needed
Explanation:
Given that:
Number of books to put on shelf = 72
Number of books per shelf = 7
Number of shelves required for all books :
Total number of books / number of books per shelf
= 72 / 7
= 10. 285
Since, only 7 books can be put on a shelf, then with 10 shelves, there will be 2 books left, hence 1 more shelf will be needed.
11 shelves are needed