The engineering team built a road. On the first day, they built 20% of the total length. On the second day, they built 1,800 meters. At this time, half of the total length has been repaired. How many meters is the total length of this road?
工程队修一条路，第一天修了全长的20%，第二天修了1800米，这时已经修了全长的一半，这条路的全长是多少米？
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">20 / 100</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">(1/2) - (1/5)</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">1_800 / (3/10)</gadget>
<output>6_000</output>

<result>6_000</result>