A road and bridge company has built a road, which has already built 1/3 of its full length. At this time, it is still 2 kilometers away from the midpoint. How many kilometers is the total length of this road?
某路桥公司修一条公路，已经修了全长的(1/3)，这时距离中点还有2千米，这条公路全长多少千米？
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">(1/2) - (1/3)</gadget>
<output>1/6 = around 0.166667</output>

<gadget id="calculator">2 / (1/6)</gadget>
<output>12</output>

<result>12</result>