If one side of a square is reduced by 4cm and the opposite side is increased by 11cm, the square becomes a trapezoid. The ratio of the upper and lower bases of the trapezoid is 4:9. Find the area of the trapezoid?
把一个正方形一条边减少4cm，对边增加11cm，正方形就变成梯形，梯形上下底的比4：9，求梯形的面积？
<gadget id="calculator">44 + 36</gadget>
<output>80</output>

<gadget id="calculator">80 / 5</gadget>
<output>16</output>

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

<gadget id="calculator">16 + 11</gadget>
<output>27</output>

<gadget id="calculator">12 + 27</gadget>
<output>39</output>

<gadget id="calculator">16 / 2</gadget>
<output>8</output>

<gadget id="calculator">39 * 8</gadget>
<output>312</output>

<result>312</result>