The area of a trapezoid is 45cm**2, the length of the upper base is 5cm, and the height of the lower base is 10cm.
一个梯形的面积是45cm**2，上底长5cm，下底是10cm高是多少cm．
<gadget id="calculator">5 + 10</gadget>
<output>15</output>

<gadget id="calculator">2 / 15</gadget>
<output>2/15 = around 0.133333</output>

<gadget id="calculator">45 * (2/15)</gadget>
<output>6</output>

<result>6</result>