Two classes in the fifth grade planted trees, with 36 students in the first class and 44 students in the second class. On average, every 4 students planted a tree together. How many trees can be planted in total?
五年级两个班去植树，一班36人，二班44人，平均每4个同学合种一棵树，一共可以种多少棵树？
<gadget id="calculator">36 + 44</gadget>
<output>80</output>

<gadget id="calculator">80 / 4</gadget>
<output>20</output>

<result>20</result>