A trapezoidal land, the upper base is 15.5 meters long, the lower base is 24.5 meters long, and the height is 5 meters. How many trees can be planted per 2 square meters?
一块梯形地，上底长15.5米，下底长24.5米，高5米．每2平方米栽一棵树，可以载多少棵树？
<gadget id="calculator">15.5 + 24.5</gadget>
<output>40</output>

<gadget id="calculator">5 / 2 / 2</gadget>
<output>5/4 = around 1.25</output>

<gadget id="calculator">40 * (5/4)</gadget>
<output>50</output>

<result>50</result>