数学题：客车和货车分别从A B两站同时相向开出，5小时后相遇。相遇后，两车仍按原速度前进，当他们相距196千米时，货车行了全程的80%，客车已行的路程与未行的路程比是3：2，求AB两站的路程。这个谁会？

数学题解答：“客车已行的路程也未行的路之比是3：2”，说明客车已行全程的3÷（3+2）＝3/5，与货车行的80%加起来比全程多了：3/5 + 80% – 1 ＝40%。

而两车现在的距离就是全程的40%，所以全程是：

196 ÷ 40% ＝490（千米）

答：AB两站的路程是490千米。

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