Cars A and B start from places A and B at the same time and drive toward each other. After 3.5 hours, the two cars met on the way. It is known that the distance between the two places is 287 kilometers, and car A travels 40 kilometers per hour. How many kilometers does car B travel per hour?
甲、乙两车从A、B两地同时出发相向而行．经过3.5小时两车在途中相遇．已知两地相距287千米，甲车每小时行驶40千米．乙车每小时行驶多少千米？
<gadget id="calculator">287 / 3.5</gadget>
<output>82</output>

<gadget id="calculator">82 - 40</gadget>
<output>42</output>

<result>42</result>