The Young Pioneers planted trees on Arbor Day. They planted 180 trees on the first day, and 315 trees on the second and third days. How many trees are planted on average per day? How many.
植树节少先队员种树，第一天种了180棵、第二天、第三天共种了315棵，平均每天种多少棵？多少．
<gadget id="calculator">180 + 315</gadget>
<output>495</output>

<gadget id="calculator">495 / 3</gadget>
<output>165</output>

<result>165</result>