Both cars A and B start from Shanghai to Hangzhou. Car B starts from the same place after driving 60 kilometers. Car B travels an average of 104.5 kilometers per hour. After 3 hours, car B catches up with car A. How many kilometers do you travel?
甲乙两车都从上海出发去杭州，甲车开出60千米后乙车从同一地点出发，乙车平均每小时行104.5千米，3小时后乙车追上甲车，甲车平均每小时行多少千米？
<gadget id="calculator">3 * 104.5</gadget>
<output>313.5</output>

<gadget id="calculator">313.5 - 60</gadget>
<output>253.5</output>

<gadget id="calculator">253.5 / 3</gadget>
<output>84.5</output>

<result>84.5</result>