The volume of the frustrum is the difference in the volumes of these two pyramids: <span>30 * 5^2 / 3 - 18 * 3^2 / 3 </span> <span>= 750/3 - 162/3 </span> <span>= 250 - 54 </span> <span>= 196 cubic inches. </span> You're Answer is <span>A- 196 cu in.</span>
