A passenger car and a freight car start from places A and B at the same time and drive towards each other. The speed ratio of the passenger car and the freight car is 5:7. Finally, the two cars meet at a distance of 30 kilometers from the midpoint. What is the total length of the two places A and B in kilometers?
客车和货车同时从甲、乙两地出发相向而行，客车和货车的速度比是5：7，最后两车在距离中点30千米处相遇，甲、乙两地全长多少千米？
<gadget id="calculator">1 / 2</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">5 + 7</gadget>
<output>12</output>

<gadget id="calculator">5 / 12</gadget>
<output>5/12 = around 0.416667</output>

<gadget id="calculator">(1/2) - (5/12)</gadget>
<output>1/12 = around 0.083333</output>

<gadget id="calculator">30 / (1/12)</gadget>
<output>360</output>

<result>360</result>