Cars A and B are traveling in the same direction at the same time from two places 140 kilometers apart. Car A is in front and is traveling 45 kilometers per hour; Car B is behind and is traveling 65 kilometers per hour. It will take several hours for car B to catch up with car A. ?
甲乙两车从相距140千米的两地同时同向而行，甲车在前，每小时行驶45千米；乙车在后，每小时行驶65千米，乙车追上甲车需要几小时？
<gadget id="calculator">65 - 45</gadget>
<output>20</output>

<gadget id="calculator">140 / 20</gadget>
<output>7</output>

<result>7</result>