The radius of the small circle is 3 cm, the radius of the large circle is 4 cm, and the area of the small circle is ((())/(())) of the area of the large circle.
小圆的半径为3厘米，大圆的半径为4厘米，小圆的面积是大圆面积的((())/(()))．
<gadget id="calculator">3 ** 2</gadget>
<output>9</output>

<gadget id="calculator">4 ** 2</gadget>
<output>16</output>

<gadget id="calculator">9 / 16</gadget>
<output>9/16 = around 0.5625</output>

<result>9/16 = around 0.5625</result>