Students in Chengdong Primary School do morning exercises. 21 students line up in a row. The distance between two adjacent students is equal. The distance from the first person to the last person is 40 meters. What is the distance between two adjacent students? rice?
城东小学的同学们做早操，21个同学排成一排，每相邻的两个同学之间的距离相等，第一个人到最后一个人的距离是40米，相邻两个人间距多少米？
<gadget id="calculator">21 - 1</gadget>
<output>20</output>

<gadget id="calculator">40 / 20</gadget>
<output>2</output>

<result>2</result>