The distance between A and B is 20 kilometers. What is the centimeter drawn on a map with a scale of 1:500000?
甲、乙两地相距20千米，画在比例尺是1：500000的地图上是多少厘米．
<gadget id="calculator">1 / 500_000</gadget>
<output>1/500_000 = around 0.000002</output>

<gadget id="calculator">20 * 100_000 * (1/500_000)</gadget>
<output>4</output>

<result>4</result>