On a map with a scale of 1:5,000,000, the distance from city A to city B is 9 cm. How many kilometers are the actual distance between cities A and B?
在比例尺是1：5000000的地图上量得A城到B城的距离为9厘米，A、B两城实际相距多少千米？
<gadget id="calculator">1 / 5_000_000</gadget>
<output>1/5_000_000 = around 0</output>

<gadget id="calculator">9 / (1/5_000_000) / 100_000</gadget>
<output>450</output>

<result>450</result>