The furniture factory sold 3,850 beds last month, leaving 2,140 beds left. Among the beds produced last month, there were 2,700 iron beds, and the rest were wooden beds. How many wooden beds are produced?
家具厂上个月生产的床，卖出了3850张，还剩2140张．上个月生产的床中有铁床2700张，其余的是木床．生产的木床有多少张？
<gadget id="calculator">2_140 - 2_700</gadget>
<output>-560</output>

<gadget id="calculator">3_850 + (-560)</gadget>
<output>3_290</output>

<result>3_290</result>