So I would say 4/18 but it could probably be 18/81 to
Answer:
12 books
Step-by-step explanation:
Since she has $15 and books come in a pack of four for $5, we can divide her money by the cost to see how many she can get ($15/$5) which gets us 3. but we have to remember the books come in a pack of four so we must multiply 3x4=12 books.
840=2 times 2 times 2 times 3 times 5 times 7