Guangming Primary School carried out tree planting week activities, and planted a total of 217 trees within a week. How many trees are planted per day on average?
光明小学开展植树周活动，在一周内一共植树217棵，平均每天植多少棵？
<gadget id="calculator">217 / 7</gadget>
<output>31</output>

<result>31</result>