Teacher Wang spent 378 yuan to buy 3 basketballs, 152 yuan to buy 2 pairs of badminton rackets, and paid 550 yuan to the salesperson. How much should I get back?
王老师买3个篮球用去378元，买2副羽毛球拍用去152元，付给售货员550元，应找回多少钱？
<gadget id="calculator">550 - 378 - 152</gadget>
<output>20</output>

<result>20</result>