Two cylinders of equal height, the ratio of the radii of their bases is 2:3, the sum of their volumes is 65 cubic centimeters, what is the difference in their volumes in cubic centimetres?
两个等高的圆柱，底面半径比为2：3，它们的体积之和为65立方厘米，它们的体积相差多少立方厘米．
<gadget id="calculator">4 + 9</gadget>
<output>13</output>

<gadget id="calculator">4 / 13</gadget>
<output>4/13 = around 0.307692</output>

<gadget id="calculator">65 * (4/13)</gadget>
<output>20</output>

<gadget id="calculator">65 - 20</gadget>
<output>45</output>

<gadget id="calculator">45 - 20</gadget>
<output>25</output>

<result>25</result>