A cylinder and a cone have the same base and height, the difference between their volumes is 6.28 cubic centimeters, what is the sum of their volumes in cubic centimeters?
一个圆柱和一个圆锥等底等高，它们的体积之差是6.28立方厘米，它们的体积之和是多少立方厘米．
<gadget id="calculator">6.28 * 2</gadget>
<output>12.56</output>

<result>12.56</result>