Class 1, Grade 3 in our school was divided into 2 groups, with 4 people in each group, and they planted 144 trees on Arbor Day. How many trees are planted per person on average?
我校三年级1班分成2个小组，每个小组有4人，他们在植树节共植树144棵．平均每人植树多少棵？
<gadget id="calculator">144 / 2 / 4</gadget>
<output>18</output>

<result>18</result>