The scale of a traffic map is 1:2,500,000, and the distance on the map is 3 centimeters, how many kilometers is the actual distance.
一幅交通地图的比例尺是1：2500000，量得图上是3厘米的距离，实际距离是多少千米．
<gadget id="calculator">1 / 2_500_000</gadget>
<output>1/2_500_000 = around 0</output>

<gadget id="calculator">3 / (1/2_500_000) / 100_000</gadget>
<output>75</output>

<result>75</result>