In a set of opposite sides of a square, one side is increased by 17 cm and the other side is decreased by 10 cm, thus becoming a trapezoid. At this time, the length of the lower base of the trapezoid is four times that of the upper base. What is the area of the trapezoid?
正方形的一组对边中，一条边增加17厘米，另一条边减少10厘米，这样就变成了梯形．这时梯形的下底的长是上底的4倍，这个梯形的面积是多少？
<gadget id="calculator">19 / 2</gadget>
<output>19/2 = around 9.5</output>

<gadget id="calculator">45 * (19/2)</gadget>
<output>855/2 = around 427.5</output>

<result>855/2 = around 427.5</result>