On a circular wooden board with a diameter of 10 decimeters, take a largest square, what is the area of the square decimeters?
在直径是10分米的圆木板上，取一个最大正方形，正方形面积是多少平方分米．
<gadget id="calculator">10 / 2</gadget>
<output>5</output>

<gadget id="calculator">10 * 5</gadget>
<output>50</output>

<result>50</result>