If the upper base of a trapezoid is increased by 8 decimeters, it becomes a rectangle, and the area increases by 36 square decimeters. If the lower base of the trapezoid is reduced to one point, the area is reduced by 54 square decimeters. What is the area of this trapezoid in square centimetres.
一个梯形的上底增加8分米，就成了一个长方形，面积增加36平方分米．如果梯形的下底缩小到一点，面积就减少54平方分米．这个梯形的面积是多少平方分米．
<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">2 / 9</gadget>
<output>2/9 = around 0.222222</output>

<gadget id="calculator">54 * (2/9)</gadget>
<output>12</output>

<gadget id="calculator">12 - 8</gadget>
<output>4</output>

<gadget id="calculator">4 + 12</gadget>
<output>16</output>

<gadget id="calculator">9 / 2</gadget>
<output>9/2 = around 4.5</output>

<gadget id="calculator">16 * (9/2)</gadget>
<output>72</output>

<result>72</result>