Two teams, A and B, jointly dig a tunnel. Team A digs 150 meters per month, and Team B digs 220 meters per month. The two teams are working at the same time, and it will be completed in 9 months. How long is the tunnel?
甲乙两队共同凿一条隧道，甲队每月开凿150米，乙队每月开凿220米，两队同时施工，9个月完工，这条隧道长多少米？
<gadget id="calculator">150 + 220</gadget>
<output>370</output>

<gadget id="calculator">370 * 9</gadget>
<output>3_330</output>

<result>3_330</result>