A and B are running a race. When A reaches the full distance (2/3), the ratio of the distance traveled by B to the distance not run is 3:1. At this time, the distance between A and B is 12 kilometers. How many kilometers is the whole journey?
甲、乙两人赛跑，甲跑到全程(2/3)处时，乙跑的路程与未跑的比是3：1，这时甲乙两人相距12千米．问全程多少千米？
<gadget id="calculator">3 + 1</gadget>
<output>4</output>

<gadget id="calculator">3 / 4</gadget>
<output>3/4 = around 0.75</output>

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

<gadget id="calculator">(3/4) - (2/3)</gadget>
<output>1/12 = around 0.083333</output>

<gadget id="calculator">12 / (1/12)</gadget>
<output>144</output>

<result>144</result>