math
posted by christian .
colin is buying dirt to fill a garden bed that is a 9 foot by 16 foot rectangle. if he wants to fill it to a depth of 4 inches, how many cubic yards of dirt does he need? if dirt costs $25 per yard, how much will the project cost?

just keep track of the units so you can convert volume to dollars:
9ft * 16ft * 4in * ft/12in * yd^3/27ft^3 * $25/yd^3 = $44.44