The distance between A and B is 665 kilometers. A bus and a truck start from the two places at the same time and drive towards each other. They meet after 7 hours. The speed of the truck is 90% of the speed of the bus. How many kilometers does the bus travel per hour?
甲乙两地相距665千米，客车和货车同时分别从两地出发，相向而行，7小时后相遇，货车的速度是客车的90%，客车每小时行多少千米？
<gadget id="calculator">90 / 100</gadget>
<output>9/10 = around 0.9</output>

<gadget id="calculator">1 + (9/10)</gadget>
<output>19/10 = around 1.9</output>

<gadget id="calculator">665 / 7 / (19/10)</gadget>
<output>50</output>

<result>50</result>