The physical education teacher wants to buy sportswear for the students on the sports team. If you buy 30 sets, there is 120 yuan left, and if you buy 35 sets, there is 20 yuan left, how much is each set of sportswear?
体育老师要给运动队的同学买运动衣．如果买30套，还剩120元，买35套，还剩20元，每套运动衣多少元？
<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>