Two passenger and freight vehicles start from A and B at the same time and drive toward each other. After traveling for a while, the distance between the two vehicles is 135 kilometers. At this time, the ratio of the distance traveled to the distance between the two vehicles is 3:1. How many miles is the distance between A and B? (two methods)
客、货两车从甲、乙两地同时出发，相向而行，行了一段时间以后，两车相距135千米，这时已行的路程与两车相距路程的比是3：1．甲、乙两地的路程是多少千米？(两种方法)
<gadget id="calculator">1 / 3</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">135 / (1/3)</gadget>
<output>405</output>

<gadget id="calculator">405 + 135</gadget>
<output>540</output>

<result>540</result>