On a map with a scale of 1:2500000, the distance between Nanjing and Yangzhou is 4 cm. How many hours does it take for a car to travel from Nanjing to Yangzhou at a speed of 50 kilometers per hour?
在一幅比例尺为1：2500000的地图上，量得南京与扬州之间的距离是4厘米．一辆汽车以每小时50千米的速度从南京到达扬州需要几小时？
<gadget id="calculator">1 / 2_500_000</gadget>
<output>1/2_500_000 = around 0</output>

<gadget id="calculator">4 / (1/2_500_000) / 100_000 / 50</gadget>
<output>2</output>

<result>2</result>