The distance between A and B is 450 kilometers. A truck travels from A to B at a speed of 60 kilometers per hour. At the same time, a bus travels from B to A. After 3 hours, the two vehicles meet on the way, and the bus travels every hour. How many kilometers?
甲、乙两地相距450千米，货车以每时60千米的速度从甲地开往乙地，同时客车从乙地开往甲地，经3小时两车在途中相遇，客车每小时行多少千米？
<gadget id="calculator">450 / 3</gadget>
<output>150</output>

<gadget id="calculator">150 - 60</gadget>
<output>90</output>

<result>90</result>