The area of a trapezoid is 72 square centimeters, the upper base is 2 cm, and the lower base is 10 cm. What is the height?
一个梯形的面积是72平方厘米，上底是2厘米，下底是10厘米，那么高是多少．
<gadget id="calculator">2 + 10</gadget>
<output>12</output>

<gadget id="calculator">2 / 12</gadget>
<output>1/6 = around 0.166667</output>

<gadget id="calculator">72 * (1/6)</gadget>
<output>12</output>

<result>12</result>