A cylinder of steel is 1.8 meters long. If it is cut into three equal small cylinders on average, the surface area will increase by 20 square decimeters. A cubic decimeter of steel weighs 7.8 kilograms, how many kilograms does this steel originally weigh?
一根圆柱体钢材长1.8米，如果将它平均截成相等的3个小圆柱，表面积就增加了20平方分米．每立方分米钢重7.8千克，求这根钢材原来重多少千克？
<gadget id="calculator">2 * 2</gadget>
<output>4</output>

<gadget id="calculator">20 / 4</gadget>
<output>5</output>

<gadget id="calculator">1.8 * 10</gadget>
<output>18</output>

<gadget id="calculator">5 * 18 * 7.8</gadget>
<output>702</output>

<result>702</result>