The sum of the volumes of cubes A and B is 81 cubic decimeters. The edge length of cube A is (1/2) the edge length of cube B. So, what is the volume of cube A in cubic decimeters?
甲、乙两个正方体的体积之和是81立方分米．甲正方体的棱长是乙正方体棱长的(1/2)．那么，甲正方体的体积是多少立方分米？
<gadget id="calculator">1 + 8</gadget>
<output>9</output>

<gadget id="calculator">1 / 9</gadget>
<output>1/9 = around 0.111111</output>

<gadget id="calculator">81 * (1/9)</gadget>
<output>9</output>

<result>9</result>