Two trains A and B leave at the same time from two places 560 kilometers apart and meet each other in 4 hours. Car A travels 68 kilometers per hour, how many kilometers per hour does Car B travel?
甲、乙两列火车同时从相距560千米的两地相向开出，4小时相遇．甲车每小时行68千米，乙车每小时行多少千米？
<gadget id="calculator">560 / 4</gadget>
<output>140</output>

<gadget id="calculator">140 - 68</gadget>
<output>72</output>

<result>72</result>