Guangming Elementary School organized a table tennis competition with 168 participants. The teacher divided the participating players into 2 groups, and each group was divided into 4 groups. How many people are there on average in each group?
光明小学组织乒乓球比赛，有168人参加，老师将参赛队员分成2个大组，每个大组又分成4个小组，平均每个小组有多少人？
<gadget id="calculator">168 / 2 / 4</gadget>
<output>21</output>

<result>21</result>