An express train and a slow train leave opposite to each other at the same time. The express train travels 78 kilometers per hour, and the slow train travels 62 kilometers per hour. The two trains meet 4.5 hours after departure. How many kilometers is the railway between the two places?
一列快车和一列慢车同时从两地相对开出，快车每小时行78千米，慢车每小时行62千米，两车出发后4.5小时相遇，两地之间的铁路长多少千米？
<gadget id="calculator">78 + 62</gadget>
<output>140</output>

<gadget id="calculator">140 * 4.5</gadget>
<output>630</output>

<result>630</result>