The distance between the volleyball court and the football field is 800 cm. On a map with a scale of 1:20000, how many cm should be drawn?
排球馆与足球场相距800cm，在一幅比例尺是1：20000的地图上，应该画多少cm？
<gadget id="calculator">800 * 100</gadget>
<output>80_000</output>

<gadget id="calculator">1 / 20_000</gadget>
<output>1/20_000 = around 0.00005</output>

<gadget id="calculator">80_000 * (1/20_000)</gadget>
<output>4</output>

<result>4</result>