A passenger car and a truck start from places A and B, which are 600 kilometers apart, at the same time, drive toward each other, and meet each other 6 hours later. The passenger car travels 40 kilometers per hour, how many kilometers per hour does the truck travel?
客车和货车从相距600千米的甲、乙两地同时出发，相向而行，6小时后相遇．客车每小时行驶40千米，货车每小时行驶多少千米？
<gadget id="calculator">600 / 6</gadget>
<output>100</output>

<gadget id="calculator">100 - 40</gadget>
<output>60</output>

<result>60</result>