Xiaoxiao measured the circumference of the trunk of a tree is 125.6 cm, what is the area of the cross section of the trunk in square decimeters?
笑笑测得一棵树树干的周长是125.6厘米，则树干的横截面的面积是多少平方分米．
<gadget id="calculator">125.6 / 2 / 3.14</gadget>
<output>20</output>

<gadget id="calculator">20 ** 2</gadget>
<output>400</output>

<gadget id="calculator">400 / 100</gadget>
<output>4</output>

<gadget id="calculator">3.14 * 4</gadget>
<output>12.56</output>

<result>12.56</result>