The actual distance of 150 km is represented on a map by a line segment 3 cm long. On this map, the distance between A and B is 12.5 cm. Find the actual distance between A and B.
在一幅地图上用3厘米长的线段表示150千米的实际距离．在这幅地图上量得甲、乙两地的距离为12.5厘米．求甲、乙两地的实际距离．
<gadget id="calculator">150 * 100_000</gadget>
<output>15_000_000</output>

<gadget id="calculator">3 / 15_000_000</gadget>
<output>1/5_000_000 = around 0</output>

<gadget id="calculator">12.5 / (1/5_000_000) / 100_000</gadget>
<output>625</output>

<result>625</result>