A cylinder and a cone have the same base area and the same height. The sum of their volumes is 12.8 cubic centimeters. What is the difference between their volumes in cubic centimeters?
一个圆柱和一个圆锥的底面积相等，高也相等，他们的体积之和是12.8立方厘米，它们的体积之差是多少立方厘米．
<gadget id="calculator">3 + 1</gadget>
<output>4</output>

<gadget id="calculator">12.8 / 4</gadget>
<output>3.2</output>

<gadget id="calculator">12.8 - 3.2</gadget>
<output>9.6</output>

<gadget id="calculator">9.6 - 3.2</gadget>
<output>6.4</output>

<result>6.4</result>