The road repair team built a road. On the first day, they repaired 30% of the total length, on the second day they repaired 1/2 of the total length, and on the second day they repaired 300 meters more than the first day. How long is this road in meters?
修路队修一条公路，第一天修了全长的30%，第二天修了全长的(1/2)，第二天比第一天多修了300米，这条公路全长多少米？
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">30 / 100</gadget>
<output>3/10 = around 0.3</output>

<gadget id="calculator">(1/2) - (3/10)</gadget>
<output>1/5 = around 0.2</output>

<gadget id="calculator">300 / (1/5)</gadget>
<output>1_500</output>

<result>1_500</result>