passenger train departs from Station A at a speed of 90 kilometers per hour and arrives at Station B in 4 hours. A train departs from Station B and arrives at Station A in 6 hours. If two cars depart from Station A and Station B at the same time and drive toward each other, how many hours later will the two cars meet?
一列客车以每小时90千米的速度从甲站出发，4小时可到达乙站，有一列货车从乙站开出，6小时可以到达甲站．如果两车同时从甲、乙两站出发，相向而行，几小时后两车相遇？
<gadget id="calculator">4 / 6</gadget>
<output>2/3 = around 0.666667</output>

<gadget id="calculator">90 * (2/3)</gadget>
<output>60</output>

<gadget id="calculator">60 + 90</gadget>
<output>150</output>

<gadget id="calculator">4 / 150</gadget>
<output>2/75 = around 0.026667</output>

<gadget id="calculator">90 * (2/75)</gadget>
<output>12/5 = around 2.4</output>

<result>12/5 = around 2.4</result>