A conical block of iron has a base radius of 5dm and a height of 6dm. A cubic decimeter of iron weighs 7.8 kilograms. How much does this piece of iron weigh in kilograms?
一个圆锥形铁块，底面半径是5dm，高6dm．每立方分米铁重7.8千克，这个铁块重多少千克？
<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">5 ** 2</gadget>
<output>25</output>

<gadget id="calculator">(1/3) * 3.14 * 25 * 6 * 7.8</gadget>
<output>1_224.6</output>

<result>1_224.6</result>