10 cm long rope is wound 10 times around a thin tube, and the remaining 0.58 cm is what is the outer diameter of the thin tube.
将一根10厘米长的绳子绕一根细管10圈，余下0.58厘米，细管的外直径是多少．
<gadget id="calculator">10 - 0.58</gadget>
<output>9.42</output>

<gadget id="calculator">9.42 / 10 / 3.14</gadget>
<output>0.3</output>

<result>0.3</result>