Put the wheat in a conical wheat pile with an area of 7.8 square meters and a height of 1.5 meters into a cylindrical grain storage with a height of 1.3 meters, which is just full. How many square meters is the bottom area of this grain storage?
把一个占地面积为7.8平方米，高1.5米的圆锥形小麦堆的小麦装进一个高1.3米的圆柱体粮囤中，正好装满．这个粮囤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">1.5 / 1.3</gadget>
<output>1.153846</output>

<gadget id="calculator">(1/3) * 7.8 * 1.153846</gadget>
<output>3</output>

<result>3</result>