From City A to City B, it took 12 hours to ride a bicycle, traveling 5 kilometers per hour; the speed of an electric bicycle is 4 times that of a bicycle, how long does it take to ride an electric bicycle from City A to City B?
从甲城到乙城，骑自行车用了12小时，每小时行5千米；电动自行车的速度是自行车的4倍，骑电动自行车从甲城到乙城要用多长时间？
<gadget id="calculator">5 * 4</gadget>
<output>20</output>

<gadget id="calculator">12 / 20</gadget>
<output>3/5 = around 0.6</output>

<gadget id="calculator">5 * (3/5)</gadget>
<output>3</output>

<result>3</result>