To build a road, the unrepaired length is 4 times the repaired length. If another 200 meters are repaired, the unrepaired length is twice the repaired length. How many meters is this road?
修一条公路，未修的长度是已修长度的4倍．如果再修200米，未修的长度就是已修长度的2倍．这条公路长多少米？
<gadget id="calculator">4 / 5</gadget>
<output>4/5 = around 0.8</output>

<gadget id="calculator">2 / 3</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">(4/5) - (2/3)</gadget>
<output>2/15 = around 0.133333</output>

<gadget id="calculator">200 / (2/15)</gadget>
<output>1_500</output>

<result>1_500</result>