Answer:
First from 18, you count to 23. So, 19, 20, 21, 22, 23. There were only 5 more pounds needed, so it would be, 1 full package of 18 pounds and 1 quarter of a package (I think), because it is not a full package, another full package of 18 would be 36 pounds. I hope this helped! [It might not]