To build a road, the ratio of the kilometers that have been repaired to the kilometers that have not been repaired is 3:5. If another 12 kilometers are repaired, the ratio of the repaired and unrepaired kilometers is 9:11. How many kilometers is this road in total?
修一条路，已修和未修的千米数比是3：5．如果再修12千米，则已修的和未修的千米数比为9：11．这条路共长多少千米？
<gadget id="calculator">11 + 9</gadget>
<output>20</output>

<gadget id="calculator">9 / 20</gadget>
<output>9/20 = around 0.45</output>

<gadget id="calculator">3 + 5</gadget>
<output>8</output>

<gadget id="calculator">3 / 8</gadget>
<output>3/8 = around 0.375</output>

<gadget id="calculator">(9/20) - (3/8)</gadget>
<output>3/40 = around 0.075</output>

<gadget id="calculator">12 / (3/40)</gadget>
<output>160</output>

<result>160</result>