On a map with a scale of 1:5,000,000, the measured distance between the two places is 3 cm. What is the actual distance in kilometers between the two places?
在一幅比例尺是1：5,000,000的地图上，量得两地间的距离是3厘米，两地间的实际距离是多少千米．
<gadget id="calculator">1 / 5_000_000</gadget>
<output>1/5_000_000 = around 0</output>

<gadget id="calculator">3 / (1/5_000_000) / 100_000</gadget>
<output>150</output>

<result>150</result>