The sum of the upper and lower bases of a trapezoid is 160 cm, and the height is 70 cm. What is the area of the trapezoid?
一个梯形，上下底的和是160厘米，高是70厘米，这个梯形的面积是多少平方分米．
<gadget id="calculator">70 / 2</gadget>
<output>35</output>

<gadget id="calculator">160 * 35</gadget>
<output>5_600</output>

<gadget id="calculator">5_600 / 100</gadget>
<output>56</output>

<result>56</result>