On Arbor Day, the third grade class planted 64 trees, and the number of trees planted by the third grade class was four times that of the first grade class, so how many trees were planted by the first grade class
植树节那天，三年级一班植树64棵，三年级一班植树的棵树是一年级一班的4倍，则一年级一班植树的棵树是多少棵
<gadget id="calculator">64 / 4</gadget>
<output>16</output>

<result>16</result>