On a map with a scale of 1:5,000,000, the distance between A and B is 4.5cm. If a car travels at 90 km/h, how long does it take to travel from A to B?
在比例尺是1：5000000的地图上，量得甲乙两城市之间的距离是4.5cm，如果一辆汽车的速度是90千米/时，那么从甲城到乙城用几小时？
<gadget id="calculator">1 / 5_000_000</gadget>
<output>1/5_000_000 = around 0</output>

<gadget id="calculator">4.5 / (1/5_000_000) / 100_000 / 90</gadget>
<output>2.5</output>

<result>2.5</result>