During the holidays, students collect compositions. There are 4 groups in our class, and the number of each group is equal. Each person collected 15 compositions. The teacher counted, the whole class has collected 720 compositions, how many people are there in each group?
假期同学们收集作文，我们班有4个小组，每个小组人数相等．每人收集了15篇作文．老师统计了一下，全班一共收集了720篇作文，每组有多少人？
<gadget id="calculator">720 / 15 / 4</gadget>
<output>12</output>

<result>12</result>