On a map with a scale of 1:20000, and the distance on the map is 5 cm, what is the actual distance in kilometers between the two places?
在比例尺是1：20000的地图上，图上距离是5厘米，则两地实际距离是多少千米．
<gadget id="calculator">1 / 20_000</gadget>
<output>1/20_000 = around 0.00005</output>

<gadget id="calculator">5 / (1/20_000)</gadget>
<output>100_000</output>

<gadget id="calculator">100_000 / 100_000</gadget>
<output>1</output>

<result>1</result>