The ratio of the mileage of the track laid to the mileage of the track that has not been laid is 1:3, and if another 329.5 kilometers are laid, it will be 50% of the total length. How many meters is the total length?
京泸高铁已铺轨里程与未铺轨里程的比是1：3，再铺329.5千米则正好铺完全程的50%，问全长多少米？
<gadget id="calculator">50 / 100</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">1 + 3</gadget>
<output>4</output>

<gadget id="calculator">1 / 4</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">(1/2) - (1/4)</gadget>
<output>1/4 = around 0.25</output>

<gadget id="calculator">329.5 / (1/4)</gadget>
<output>1_318</output>

<result>1_318</result>