On a map with a scale of 1:5000000, the distance between A and B is 9 cm. The passenger car and the truck depart from the two cities A and B at the same time and meet at 6 o'clock. The speed ratio of passenger cars and trucks is 8:7. How many kilometers does the bus travel per hour?
在一幅比例尺是1：5000000的地图上，量得A、B两个城市间的距离是9厘米．客车和货车同时从A、B两城相向开出，6时相遇．客车和货车的速度比是8：7．客车每时行多少千米？
<gadget id="calculator">450 / 6</gadget>
<output>75</output>

<gadget id="calculator">8 / 15</gadget>
<output>8/15 = around 0.533333</output>

<gadget id="calculator">75 * (8/15)</gadget>
<output>40</output>

<result>40</result>