If the radius of the large circle is twice the radius of the small circle, what is the area of the small circle equal to the area of the large circle?
大圆半径是小圆半径的2倍，则小圆面积是大圆面积的多少
<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<result>1/4 = around 0.25</result>