On a map with a scale of 1:6,000,000, the distance between Nanjing and Beijing is measured to be 15 centimeters. What is the actual distance between Nanjing and Beijing in kilometers?
在比例尺是1：6000000的地图上，量得南京到北京的距离是15厘米，南京到北京的实际距离大约是多少千米千米．
<gadget id="calculator">1 / 6_000_000</gadget>
<output>1/6_000_000 = around 0</output>

<gadget id="calculator">15 / (1/6_000_000) / 100_000</gadget>
<output>900</output>

<result>900</result>