The area of a trapezoid is 36 square meters, the height is 8 meters, the upper base is 4 meters, and the lower base is how many meters.
一个梯形的面积是36平方米，高是8米，上底是4米，下底是多少米．
<gadget id="calculator">2 / 8</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">36 * (1/4)</gadget>
<output>9</output>

<gadget id="calculator">9 - 4</gadget>
<output>5</output>

<result>5</result>