The road repair team repaired a section of road, the ratio of the length of the repaired to the unrepaired was 2:3, and after another 140 meters, the length of the repaired was three times that of the unrepaired. How long is this road in meters?
修路队修一段公路，已修的与未修的长度比是2：3，再修140米后已修的是未修的3倍．这段公路长多少米．
<gadget id="calculator">3 + 1</gadget>
<output>4</output>

<gadget id="calculator">3 / 4</gadget>
<output>3/4 = around 0.75</output>

<gadget id="calculator">2 + 3</gadget>
<output>5</output>

<gadget id="calculator">2 / 5</gadget>
<output>2/5 = around 0.4</output>

<gadget id="calculator">(3/4) - (2/5)</gadget>
<output>7/20 = around 0.35</output>

<gadget id="calculator">140 / (7/20)</gadget>
<output>400</output>

<result>400</result>