Ms. Cohen can buy 12 boxes of crayons with the rest of her money. In the question it states she only wants to buy 1 poster not more than one so if she buys 1 poster that's
30-5-25
and than you can just count up by 2 till you get the closest to 25
And also , can people please stop posting did you get the answer yet, just so you could get the points. They only take two answers, and that's a waste of somebody who could've answered or helped.