The perimeter of a square is 80dm, what is its area in square meters?
一个正方形的周长是80dm，它的面积是多少平方米？
<gadget id="calculator">80 / 4</gadget>
<output>20</output>

<gadget id="calculator">80 / 4 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">20 * (1/5)</gadget>
<output>4</output>

<result>4</result>