The road construction team wanted to build a 12,610-meter road. It was originally planned to be completed in 30 days, but the actual construction was 485 meters per day. How many days in advance can this be done?
修路队要修一条12610米的路，原计划30天修完，实际每天修485米．这样可提前几天完成？
<gadget id="calculator">12_610 / 485</gadget>
<output>26</output>

<gadget id="calculator">30 - 26</gadget>
<output>4</output>

<result>4</result>