Okay. so we need 15 2/5 pound bags. We'll calculate how many pounds that actually comes to. Our problem is 15x2/5. Using cross simplification, our problem becomes 3x2. 3x2=6. We need 6 pounds. That means that we must have 6 1-pound bags to fit with no leftovers.
You forgot to add in your height to your question. To find your area you need to do 8 + 14 and get 22 then you nee to do the height divided by two. If you give me the height of the triangle I can tell you the area.