On a map with a scale of 1:800,000, the distance between A and B is 5 cm. What is the actual distance between A and B in kilometers?
在一幅比例尺是1：800000的地图上，量得甲、乙两地的距离是5厘米，甲、乙两地的实际距离是多少千米．
<gadget id="calculator">1 / 800_000</gadget>
<output>1/800_000 = around 0.000001</output>

<gadget id="calculator">5 / (1/800_000) / 100_000</gadget>
<output>40</output>

<result>40</result>