A train of passenger cars and a train of freight cars depart from A and B at the same time. After 3 hours, the distance between the two cars is still 135 km. After driving for another 2 hours, the distance between the two cars is 135 km. The speed ratio is 5:4, how many kilometers does the bus travel per hour?
一列客车和一列货车同时从甲、乙两地相向开出，3小时后两车之间还相距135千米，接着又行驶了2小时，两车之间又相距135千米，客车和货车的速度比是5：4，客车每小时行多少千米？
<gadget id="calculator">135 + 135</gadget>
<output>270</output>

<gadget id="calculator">270 / 2</gadget>
<output>135</output>

<gadget id="calculator">5 + 4</gadget>
<output>9</output>

<gadget id="calculator">5 / 9</gadget>
<output>5/9 = around 0.555556</output>

<gadget id="calculator">135 * (5/9)</gadget>
<output>75</output>

<result>75</result>