Example 6: The distance between the two cities is 138 kilometers. Two people, A and B, start from the two cities by bicycle and walk towards each other. A travels 13 kilometers per hour, and B travels 12 kilometers per hour. During the journey, B delays for 1 hour due to waiting for the car to be repaired, and then continues to travel and meets A. Find out how many hours have elapsed from departure to encounter?
例6：两城市相距138千米，甲乙两人骑自行车分别从两城出发，相向而行．甲每小时行13千米，乙每小时行12千米，乙在行进中因修车候车耽误1小时，然后继续行进，与甲相遇．求从出发到相遇经过几小时？
<gadget id="calculator">138 - 13</gadget>
<output>125</output>

<gadget id="calculator">13 + 12</gadget>
<output>25</output>

<gadget id="calculator">125 / 25</gadget>
<output>5</output>

<gadget id="calculator">5 + 1</gadget>
<output>6</output>

<result>6</result>