tape recorder is 485 yuan. Teacher Wang bought 2 sets and paid 1,000 yuan. How much should I get back?
一台收录机485元，王老师买了2台，付了1000元，应找回多少元钱？
<gadget id="calculator">485 * 2</gadget>
<output>970</output>

<gadget id="calculator">1_000 - 970</gadget>
<output>30</output>

<result>30</result>