The railway from Dalian to Changchun is 780 kilometers long, and the two trains depart from the two places at the same time, running towards each other. One of them travels 58 kilometers per hour, and the other travels 72 kilometers per hour. How long did it take to meet? (solution by equation)
大连到长春的铁路长780千米，两列火车同时从两地开出，相向而行．其中一列每小时行58千米，另一列每小时行72千米．经过几时相遇？(用方程解)
<gadget id="calculator">72 + 58</gadget>
<output>130</output>

<gadget id="calculator">780 / 130</gadget>
<output>6</output>

<result>6</result>