The distance between A and B is 446 kilometers. The fast and slow cars leave from A and B at the same time. The fast car travels 68 kilometers per hour, and the slow car travels 35 kilometers per hour. The slow car stops for half an hour for repairs. Hours, how many hours have elapsed from the departure of the two vehicles to the meeting of the two vehicles?
甲、乙两地相距446千米，快、慢两车同时从甲、乙两地相对开出，快车每小时行68千米，慢车每小时行35千米，中途慢车修车停留了半个小时，从两车出发到两车相遇共经过多少小时？
<gadget id="calculator">68 * 0.5</gadget>
<output>34</output>

<gadget id="calculator">446 - 34</gadget>
<output>412</output>

<gadget id="calculator">68 + 35</gadget>
<output>103</output>

<gadget id="calculator">412 / 103</gadget>
<output>4</output>

<gadget id="calculator">4 + 0.5</gadget>
<output>4.5</output>

<result>4.5</result>