A paper company needs to ship paper to a large printing business. The paper will be
shipped in small boxes and large boxes. The volume of each small box is 7 cubic feet
and the volume of each large box is 13 cubic feet. A total of 21 boxes of paper were
shipped with a combined volume of 231 cubic feet. Determine the number of small
boxes shipped and the number of large boxes shipped.
I need help quick!