A train of passenger cars and a train of trucks are running in opposite directions at the same time at the same time. The truck is 6 km faster than the passenger car per hour. After 3 hours, the distance between the two cars is 342 km. Find the speed of the passenger car.
一列客车和一列货车同时同地反向而行，货车每小时比客车快6千米，3小时后两车相距342千米，求客车的速度．
<gadget id="calculator">342 / 3</gadget>
<output>114</output>

<gadget id="calculator">114 - 6</gadget>
<output>108</output>

<gadget id="calculator">108 / 2</gadget>
<output>54</output>

<result>54</result>