It takes Xiaoliang 3.6 hours to ride a bicycle from place A to place B at 20 kilometers per hour. If he goes 4 kilometers per hour, how many hours will it take?
小亮骑自行车从甲地到乙地，每小时行20千米，需要3.6小时，如果每小时多行4千米，需要多少小时？
<gadget id="calculator">20 + 4</gadget>
<output>24</output>

<gadget id="calculator">3.6 / 24</gadget>
<output>0.15</output>

<gadget id="calculator">20 * 0.15</gadget>
<output>3</output>

<result>3</result>