The upper base of a trapezoid is 6 decimeters, the lower base is 9 decimeters, and the height is 2 meters. What is its area?
一个梯形上底6分米，下底9分米，高2米，它的面积是多少．
<gadget id="calculator">9 + 6</gadget>
<output>15</output>

<gadget id="calculator">2 * 10</gadget>
<output>20</output>

<gadget id="calculator">20 / 2</gadget>
<output>10</output>

<gadget id="calculator">15 * 10</gadget>
<output>150</output>

<result>150</result>