If a 30 decimeter long cuboid is cut into 5 sections, the surface area will increase by 40 square decimeters. What is the volume of this piece of wood?
一根长30分米的长方体木料，把它平均截成5段后，表面积增加40平方分米．原来这根木料的体积是多少？
<gadget id="calculator">40 / 8</gadget>
<output>5</output>

<gadget id="calculator">5 * 30</gadget>
<output>150</output>

<result>150</result>