The sum of the upper and lower bases of a trapezoid is 24 cm, which is three times the height. What is the area of the trapezoid?
一个梯形的上底和下底的长度和是24厘米，是高的3倍，这个梯形的面积是多少．
<gadget id="calculator">24 / 3</gadget>
<output>8</output>

<gadget id="calculator">8 / 2</gadget>
<output>4</output>

<gadget id="calculator">24 * 4</gadget>
<output>96</output>

<result>96</result>