The upper base of a trapezoidal wheat field is 25m, the lower base is 35m, and the area is 1140m**2. How many meters high?
一块梯形麦田的上底是25m，下底是35m，面积是1140m**2．高多少米？
<gadget id="calculator">25 + 35</gadget>
<output>60</output>

<gadget id="calculator">2 / 60</gadget>
<output>1/30 = around 0.033333</output>

<gadget id="calculator">1_140 * (1/30)</gadget>
<output>38</output>

<result>38</result>