The distance between A and B is 624km. A slow train and an express train start from the two places at the same time and go towards each other. After 2.4 hours, the two trains meet. It is known that the speed ratio of the slow train and the express train is 6:7. What is the speed of the express train?
甲、乙两地相距624km，一列慢车和一列快车同时从两地出发，相向而行，2.4h后两车相遇，已知慢车和快车的速度之比是6：7，快车的速度是多少？
<gadget id="calculator">624 / 2.4</gadget>
<output>260</output>

<gadget id="calculator">6 + 7</gadget>
<output>13</output>

<gadget id="calculator">7 / 13</gadget>
<output>7/13 = around 0.538462</output>

<gadget id="calculator">260 * (7/13)</gadget>
<output>140</output>

<result>140</result>