The distance between A and B is 480 kilometers. The express train departs from A and the slow train departs from B at the same time. It is known that the express train travels 70 kilometers per hour and the slow train travels 50 kilometers per hour. The two vehicles meet at C on the way. How many miles is the distance between C and A?
甲、乙两地相距480千米，快车从甲地，慢车从乙地，同时出发，已知快车每小时行70千米，慢车每小时行50千米，两车在途中丙地相遇，问丙地与甲地相距多少千米？
<gadget id="calculator">70 + 50</gadget>
<output>120</output>

<gadget id="calculator">480 / 120</gadget>
<output>4</output>

<gadget id="calculator">4 * 70</gadget>
<output>280</output>

<result>280</result>