Two trains, A and B, depart from two places 756 kilometers apart at the same time. It is known that train A travels 70 kilometers per hour, and train B travels 56 kilometers per hour. After how many hours do they meet?
甲乙两列火车同时从相距756千米的两地相对开出，已知甲车每小时行70千米，乙车每小时行56千米，经过几小时相遇？
<gadget id="calculator">70 + 56</gadget>
<output>126</output>

<gadget id="calculator">756 / 126</gadget>
<output>6</output>

<result>6</result>