Cut a cube part with an edge length of 20 cm into the largest cylindrical part, how to find the utilization rate of the material?
把一个棱长是20厘米的正方体零件削成一个最大的圆柱体零件，求材料的利用率？
<gadget id="calculator">20 / 2</gadget>
<output>10</output>

<gadget id="calculator">10 ** 2</gadget>
<output>100</output>

<gadget id="calculator">3.14 * 100 * 20</gadget>
<output>6_280</output>

<gadget id="calculator">20 * 20 * 20</gadget>
<output>8_000</output>

<gadget id="calculator">6_280 / 8_000</gadget>
<output>157/200 = around 0.785</output>

<gadget id="calculator">100 / 100</gadget>
<output>1</output>

<gadget id="calculator">(157/200) * 1</gadget>
<output>157/200 = around 0.785</output>

<result>157/200 = around 0.785</result>