The area of a trapezoid is 16 square decimeters, the upper base is 3 decimeters, the lower base is 5 decimeters, and the height is decimeters.
一个梯形的面积是16平方分米，上底是3分米，下底是5分米，高是多少分米．
<gadget id="calculator">3 + 5</gadget>
<output>8</output>

<gadget id="calculator">2 / 8</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">16 * (1/4)</gadget>
<output>4</output>

<result>4</result>