A cylinder of steel is 5 meters long. After cutting into three small cylinders of the same size, the surface area increases by 36 square decimeters. What is the original volume of this steel in cubic decimeters?
一个圆柱体钢材长5米，切成3个同样大小的小圆柱体后，表面积增加了36平方分米，这根钢材原来的体积是多少立方分米
<gadget id="calculator">36 / 4</gadget>
<output>9</output>

<gadget id="calculator">5 * 10</gadget>
<output>50</output>

<gadget id="calculator">9 * 50</gadget>
<output>450</output>

<result>450</result>