A trapezoid whose upper base is x decimeters long, whose lower base is twice as long as the upper base, and whose height is h decimeters, what is its area in square decimeters?
一个梯形，它上底长x分米，下底长度是上底的2倍，高是h分米，它的面积是多少平方分米．
<gadget id="calculator">3 / 2</gadget>
<output>3/2 = around 1.5</output>

<result>3/2 = around 1.5</result>