A trapezoid, it is known that the sum of the upper base and the lower base is 22 cm, and the height is 8 cm, then what is the area of the trapezoid.
一个梯形，已知上底与下底的和是22厘米，高是8厘米，那么这个梯形的面积是多少．
<gadget id="calculator">8 / 2</gadget>
<output>4</output>

<gadget id="calculator">22 * 4</gadget>
<output>88</output>

<result>88</result>