A construction team wanted to install 900 meters of sewers, and installed 300 meters in 6 days. At this speed, how many days will it take to complete the remaining tasks? (Solve with ratio)
某施工队要安装900米的下水道，6天安装了300米，照这样的速度剩下的任务，还要多少天可以完成？(用比例解)
<gadget id="calculator">900 - 300</gadget>
<output>600</output>

<gadget id="calculator">300 / 6</gadget>
<output>50</output>

<gadget id="calculator">600 / 50</gadget>
<output>12</output>

<result>12</result>