Answer: 90 textbooks
Step-by-step explanation:
everytime you multiply the number of students you multiply the books by the same number. to find how many times 72 was multiplied you divide it by 12.
72 รท 12 = 6
then multiply the original number of books (15) by 6.
15 * 6 = 90
so for every 72 students the school orders 90 textbooks