road is built with a total length of 12 kilometers, and 2 kilometers have been repaired in 4 days after starting construction. According to this calculation, how many days will it take to complete the road? (Answer with proportional knowledge)
修一条公路，总长12千米，开工4天修了2千米，照这样计算，修完这条公路还要多少天？(用比例知识解答)
<gadget id="calculator">12 - 2</gadget>
<output>10</output>

<gadget id="calculator">2 / 4</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">10 / (1/2)</gadget>
<output>20</output>

<result>20</result>