The sum of the upper and lower bases of a trapezoid is 16 meters and the height is 7 meters. What is its area?
一个梯形上下底的和是16米，高是7米，它的面积是多少．
<gadget id="calculator">7 / 2</gadget>
<output>7/2 = around 3.5</output>

<gadget id="calculator">16 * (7/2)</gadget>
<output>56</output>

<result>56</result>