The express train and the slow train leave from A and B oppositely. If the slow train drives 2 hours first, the slow train will pass 48 kilometers from the midpoint when they meet; if the express train drives 2 hours first, the distance from the midpoint will be 144 kilometers. If you leave at the same time, you can meet each other in 6 hours. How many kilometers per hour is the express train faster than the slow train?
快车和慢车从甲、乙两地相对开出，如果慢车先开2小时，两车相遇时慢车过中点48千米；若快车先开2小时，相遇时距中点144千米．如果同时开出，6小时可以相遇，快车比慢车每小时快多少千米．
<gadget id="calculator">144 * 2</gadget>
<output>288</output>

<gadget id="calculator">48 * 2</gadget>
<output>96</output>

<gadget id="calculator">288 - 96</gadget>
<output>192</output>

<gadget id="calculator">192 / 2 / 6</gadget>
<output>16</output>

<result>16</result>