This is a division problem. We're needing to find how many stamps Phil puts on each of his 9 pages, and the number of stamps needs to be equal for each page so no one page is overfilled or underfilled. Now, we divide 189/9, and we get 21. In not sure how to show long division on here. Sorry. :/
If he puts the same number of stamps on each page, and you want to know the number of stamps on each page, you just need to divide the total number of stamps by the number of pages.
