The school took a sum of money to buy a set of sportswear for each athlete of the sports team. If you buy 30 sets, you will have 120 yuan left, and if you buy 35 sets, you will have 20 yuan left. How much is each set of sportswear?
学校拿了一笔钱给体育队的运动员们每人买一套运动衣，如果买30套，还剩120元，如果买35套，还剩20元，每套运动衣多少钱？
<gadget id="calculator">120 - 20</gadget>
<output>100</output>

<gadget id="calculator">35 - 30</gadget>
<output>5</output>

<gadget id="calculator">100 / 5</gadget>
<output>20</output>

<result>20</result>