A train travels from city A to city B at a speed of 260 kilometers per hour. The distance between cities A and B is 3120 kilometers. After the speed is increased, it takes two hours to arrive. What is the speed after the acceleration?
一辆列车以每小时260千米的速度从甲城开往乙城，甲、乙两城的距离是3120千米，经过提速后比原来缩短了两小时到达．提速后速度是多少？
<gadget id="calculator">3_120 / 260</gadget>
<output>12</output>

<gadget id="calculator">12 - 2</gadget>
<output>10</output>

<gadget id="calculator">3_120 / 10</gadget>
<output>312</output>

<result>312</result>