The length of the road from A to B is 400 kilometers, how many centimeters should be drawn on a map with a scale of 1:2000000.
甲地到乙地的公路长是400千米，在比例尺是1：2000000的地图上应画多少厘米．
<gadget id="calculator">1 / 2_000_000</gadget>
<output>1/2_000_000 = around 0</output>

<gadget id="calculator">400 * 100_000 * (1/2_000_000)</gadget>
<output>20</output>

<result>20</result>