Reuse the map with a scale of 1:2500 to a scale of 1:10000 to draw a 40 cm railway on the original map, how many centimeters should be drawn on the new map.
把比例尺为1：2500的地图重新用1：10000的比例尺，画出原图上40厘米的铁路，在新图上应画多少厘米．
<gadget id="calculator">1 / 2_500</gadget>
<output>1/2_500 = around 0.0004</output>

<gadget id="calculator">40 / (1/2_500)</gadget>
<output>100_000</output>

<gadget id="calculator">1 / 10_000</gadget>
<output>1/10_000 = around 0.0001</output>

<gadget id="calculator">100_000 * (1/10_000)</gadget>
<output>10</output>

<result>10</result>