On a 1:800,000 map, the distance between two cities is measured to be 3 cm. What is the actual distance in kilometers between the two cities?
在一幅1：800000的地图上，量得两个城市之间的距离是3厘米，两城市之间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">1_000 * 100</gadget>
<output>100_000</output>

<gadget id="calculator">3 / (1/800_000) / 100_000</gadget>
<output>24</output>

<result>24</result>