Two engineering teams, A and B, are building a 2,400-meter-long road. They start work from both ends at the same time. Team A repairs 70 meters a day, and team B repairs 90 meters a day. How many days will it take to complete the road?
甲、乙两工程队修一条长2400米的公路，他们从两端同时开工，甲队每天修70米，乙队每天修90米，多少天后能够修完这条公路？
<gadget id="calculator">70 + 90</gadget>
<output>160</output>

<gadget id="calculator">2_400 / 160</gadget>
<output>15</output>

<result>15</result>