On a map with a scale of 1:4000000, a line segment of 4 cm represents the actual distance in kilometers.
在比例尺是1：4000000的地图上，4厘米的线段表示实际距离多少千米．
<gadget id="calculator">1 / 4_000_000</gadget>
<output>1/4_000_000 = around 0</output>

<gadget id="calculator">4 / (1/4_000_000) / 100_000</gadget>
<output>160</output>

<result>160</result>