The circumference of a rectangle and a circle are equal. It is known that the circumference of the circle is 31.4 cm. The ratio of the width to the length of the rectangle is 1:4. How much less is the area of the rectangle than the area of the circle?
一个长方形和一个圆的周长相等，已知圆周长是31.4厘米，长方形的宽和长的比1：4，长方形的面积比圆的面积少多少？
<gadget id="calculator">31.4 / 2</gadget>
<output>15.7</output>

<gadget id="calculator">1 + 4</gadget>
<output>5</output>

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

<gadget id="calculator">15.7 * (1/5)</gadget>
<output>3.14</output>

<gadget id="calculator">31.4 / 3.14 / 2</gadget>
<output>5</output>

<gadget id="calculator">5 ** 2</gadget>
<output>25</output>

<gadget id="calculator">3.14 * 25</gadget>
<output>78.5</output>

<gadget id="calculator">15.7 - 3.14</gadget>
<output>12.56</output>

<gadget id="calculator">12.56 * 3.14</gadget>
<output>39.4384</output>

<gadget id="calculator">78.5 - 39.4384</gadget>
<output>39.0616</output>

<result>39.0616</result>