A road has already been repaired for one third of its length, and if another 300 meters are repaired, half of the total length can be repaired. How many meters is this road?
一条公路，已经修了它的三分之一，再修300米，就能修好全长的一半，则这条公路有多少米？
<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">300 / (1/6)</gadget>
<output>1_800</output>

<result>1_800</result>