A square log with a length of 3 meters is sawed into 5 sections along the cross section, and the surface area is increased by 120 square decimeters. What is the volume of the original square log?
把一根长3米的方木沿横截面锯成5段，表面积增加120平方分米，原来这根方木的体积是多少．
<gadget id="calculator">120 / 8</gadget>
<output>15</output>

<gadget id="calculator">3 * 10</gadget>
<output>30</output>

<gadget id="calculator">15 * 30</gadget>
<output>450</output>

<result>450</result>