Divide a circle into several equal parts and put together an approximate rectangle. The perimeter of this rectangle is 24.84 cm. What is the approximate area of this circle in square centimeters?
把一个圆分成若干等分，拼成一个近似的长方形，这个长方形的周长是24.84厘米，这个圆的面积约是多少平方厘米．
<gadget id="calculator">24.84 / 8.28</gadget>
<output>3</output>

<gadget id="calculator">3 ** 2</gadget>
<output>9</output>

<gadget id="calculator">3.14 * 9</gadget>
<output>28.26</output>

<result>28.26</result>