The school holds a gymnastics competition. If there are 30 people in each row, there should be 25 rows. If there are 15 rows, how many people should be arranged in each row? (Solve with ratio)
学校进行体操比赛，如果每列30人，要排25列．如果要排15列，每列要排多少人？(用比例解)
<gadget id="calculator">30 * 25</gadget>
<output>750</output>

<gadget id="calculator">750 / 15</gadget>
<output>50</output>

<result>50</result>