The school held a queue broadcasting exercise competition, with 12 people standing in each row, exactly 20 rows. If there are 8 people in each row, how many rows should they stand in?
学校举行队列广播操比赛，每排站12人，刚好站20排．如果每排站8人，要站多少排？
<gadget id="calculator">20 / 8</gadget>
<output>5/2 = around 2.5</output>

<gadget id="calculator">12 * (5/2)</gadget>
<output>30</output>

<result>30</result>