The circumference of a circle is 25.12 decimeters, so how many decimeters is the circumference of a semicircle?
一个圆的周长是25.12分米，那么半圆的周长是多少分米？
<gadget id="calculator">25.12 / 2</gadget>
<output>12.56</output>

<gadget id="calculator">25.12 / 3.14</gadget>
<output>8</output>

<gadget id="calculator">12.56 + 8</gadget>
<output>20.56</output>

<result>20.56</result>