There is a square paper with a side length of 10 meters. If you cut four equal and largest circles on this paper, what is the sum of the areas of these four circles?
有一张边长为10米的正方形纸，如果在这张纸上剪四个相等并且最大的圆，这四个圆的面积之和约是这张纸的多少
<gadget id="calculator">10 / 2 / 2</gadget>
<output>5/2 = around 2.5</output>

<gadget id="calculator">(5/2) ** 2</gadget>
<output>25/4 = around 6.25</output>

<gadget id="calculator">10 * 10</gadget>
<output>100</output>

<gadget id="calculator">4 / 100</gadget>
<output>1/25 = around 0.04</output>

<gadget id="calculator">3.14 * (25/4) * (1/25)</gadget>
<output>0.785</output>

<result>0.785</result>