There are two cylindrical containers, A and B. Container A contains 12 liters of water, and container B is empty. Now fill the two containers with water at a rate of 1.5 liters per minute. After 4 minutes, the water level is the same. The radius of the base is 10 cm, find the area of the base of the container A.
有甲、乙两个圆柱形容器，甲容器有水12升，乙容器是空的，现在同时用每分钟1.5升的速度住两个容器注水，4分钟后水面一样高，已知乙容器的底面半径是10厘米，求甲容器的底面积．
<gadget id="calculator">1.5 * 4</gadget>
<output>6</output>

<gadget id="calculator">12 + 6</gadget>
<output>18</output>

<gadget id="calculator">10 / 10</gadget>
<output>1</output>

<gadget id="calculator">1 ** 2</gadget>
<output>1</output>

<gadget id="calculator">3.14 * 1</gadget>
<output>3.14</output>

<gadget id="calculator">4 / 3.14</gadget>
<output>1.273885</output>

<gadget id="calculator">1.5 * 1.273885</gadget>
<output>1.910827</output>

<gadget id="calculator">18 / 1.910827</gadget>
<output>9.420005</output>

<result>9.420005</result>