The total length of a road to be built is 12 kilometers, and 3600 meters were repaired 3 days before the start of construction. According to this calculation, how many days will it take to complete the road?
修一条公路总长12千米，开工前3天修了3600米，照这样计算，修完这条路还需多少天？
<gadget id="calculator">12 * 1_000</gadget>
<output>12_000</output>

<gadget id="calculator">12_000 - 3_600</gadget>
<output>8_400</output>

<gadget id="calculator">3_600 / 3</gadget>
<output>1_200</output>

<gadget id="calculator">8_400 / 1_200</gadget>
<output>7</output>

<result>7</result>