The shape of an orchard is trapezoidal, its upper base is 60 meters, its lower base is 80 meters, and its height is 30 meters. If each fruit tree occupies an area of 10 square meters, how many fruit trees are there in this orchard?
一个果园的形状是梯形，它的上底是60米，下底是80米，高是30米，如果每棵果树占地10平方米，这果园共有多少棵果树？
<gadget id="calculator">80 + 60</gadget>
<output>140</output>

<gadget id="calculator">30 / 2 / 10</gadget>
<output>3/2 = around 1.5</output>

<gadget id="calculator">140 * (3/2)</gadget>
<output>210</output>

<result>210</result>