There is a vegetable field in the shape of a trapezoid. The upper base is 13 meters, 8 meters shorter than the lower base, and the height is 50 meters. Last year, a total of 11,900 kilograms of cabbage was harvested. How many kilograms of cabbage were harvested per square meter on average?
有一块菜地为梯形，上底是13米，比下底短8米，高是50米，去年共收白菜11900千克，平均每平方米收白菜多少千克？
<gadget id="calculator">13 + 13 + 8</gadget>
<output>34</output>

<gadget id="calculator">50 / 2</gadget>
<output>25</output>

<gadget id="calculator">34 * 25</gadget>
<output>850</output>

<gadget id="calculator">11_900 / 850</gadget>
<output>14</output>

<result>14</result>