To build a 1,400-meter-long road, start to build 200 meters a day. After 2 days, the remaining tasks will be 50 meters a day. Ask: How many days will it take to finish the repair?
修一条长1400米的公路，开始每天修200米，修了2天后，余下的任务每天修50米，问：还要几天修完？
<gadget id="calculator">200 * 2</gadget>
<output>400</output>

<gadget id="calculator">1_400 - 400</gadget>
<output>1_000</output>

<gadget id="calculator">1_000 / 50</gadget>
<output>20</output>

<result>20</result>