If the radius of the base of a cylinder increases (1/2) and the height decreases (1/2), how much does the volume increase
一个圆柱体底面半径增加(1/2)，高减少(1/2)，则体积增加多少
<gadget id="calculator">1 / 8</gadget>
<output>1/8 = around 0.125</output>

<result>1/8 = around 0.125</result>