Wrap a 10 decimeter long rope around a tree once, and there is 3.72 decimeters left. What is the diameter of this tree?
将一根长10分米的绳子绕一棵树1圈，还余下3.72分米．这棵树的直径是多少分米？
<gadget id="calculator">10 - 3.72</gadget>
<output>6.28</output>

<gadget id="calculator">6.28 / 3.14</gadget>
<output>2</output>

<result>2</result>