The area of a trapezoid is 1600 cm**2, the height is 80 cm, and the upper base is 35 cm. How many centimeters is the lower base of the trapezoid?
一个梯形的面积是1600厘米**2，高是80cm，上底是35cm，那么这个梯形的下底是多少厘米？
<gadget id="calculator">2 / 80</gadget>
<output>1/40 = around 0.025</output>

<gadget id="calculator">1_600 * (1/40)</gadget>
<output>40</output>

<gadget id="calculator">40 - 35</gadget>
<output>5</output>

<result>5</result>