A conical wheat pile has a base circumference of 31.4 meters and a height of 1.8 meters. If these wheats are packed into a cylindrical grain storage, it is just full. It is known that the height of this grain storage is 10 meters, how many square meters is its bottom area?
一个圆锥形麦堆，底面周长是31.4米，高1.8米．如果把这些小麦装入一个圆柱形粮囤，正好装满．已知这个粮囤的高是10米，它的底面积是多少平方米？
<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">1.8 / 10</gadget>
<output>0.18</output>

<gadget id="calculator">(1/3) * 3.14 * 25 * 0.18</gadget>
<output>4.71</output>

<result>4.71</result>