Cars A and B start from A and B at the same time and drive towards each other, and meet each other in 6 hours. If A starts 2 hours earlier, when A and B meet, A has already passed the midpoint of AB 144 kilometers; if B starts 2 hours earlier, when A and B meet, A is still 48 kilometers away from the midpoint of AB. What is the speed difference of A and B in km/h?
甲、乙两车分别从A、B两地同时出发相向而行，6小时相遇．如果甲早出发2小时，甲乙相遇时，甲已经走过AB的中点144千米；如果乙早出发2小时，甲乙相遇时，甲还差48千米到AB的中点．甲乙的速度差是多少千米/时．
<gadget id="calculator">144 - 48</gadget>
<output>96</output>

<gadget id="calculator">96 * 2</gadget>
<output>192</output>

<gadget id="calculator">6 * 2</gadget>
<output>12</output>

<gadget id="calculator">192 / 12</gadget>
<output>16</output>

<result>16</result>