A 200-meter-long road was built, and 50 meters were built two days ago. According to this calculation, how many days will it take to complete the road? (Solve with ratio)
修一条长200米的路，前两天修了50米，照这样计算，修完这条路共用几天？(用比例解)
<gadget id="calculator">200 * 2</gadget>
<output>400</output>

<gadget id="calculator">400 / 50</gadget>
<output>8</output>

<result>8</result>