【中文版】

430为什么叫485？这背后其实是一个关于数字命名和数字系统的有趣故事。

在早期，430是中国大陆的身份证号码最后四位，而485则是在香港特别行政区使用的身份证号码最后四位。随着时间的推移，人们开始将这两个数字简称为“430”和“485”，并在一些场合使用它们来指代中国大陆和香港特别行政区。

那么，为什么430会成为中国大陆身份证号码的代表呢？这是因为在中国大陆，身份证号码是由18位数字组成的，其中最后四位数字是顺序码，用来表示同一顺序中的不同个体。而430这个数字组合在统计学上比较常见，因此在一些数据分析和处理中，人们便用430来指代中国大陆的身份证号码。

同样地，485也成为了香港特别行政区身份证号码的代表。这是因为香港特别行政区的身份证号码最后四位是顺序码，其中85这个数字组合比较常见，因此在一些场合便用485来指代香港特别行政区的身份证号码。

总之，430和485这两个数字之所以被用来指代中国大陆和香港特别行政区，是因为它们在各自的数字系统中具有特殊的意义和代表性。而在实际使用中，人们也习惯了用这两个数字来区分不同的地区和身份信息。

【英文版】

Why is 430 called 485? This is actually an interesting story about digital naming and number systems.

In the early days, 430 was the last four digits of ID numbers in mainland China, while 485 was the last four digits of ID numbers used in Hong Kong Special Administrative Region. As time went by, people started to abbreviate these two numbers as "430" and "485" and use them to refer to Mainland China and Hong Kong Special Administrative Region in some occasions.

So, why did 430 become the representative of ID numbers in Mainland China? This is because in Mainland China, ID numbers are composed of 18 digits, and the last four digits are sequential codes used to distinguish different individuals in the same sequence. The number combination of 430 is relatively common in statistics, so in some data analysis and processing, people use 430 to refer to ID numbers in Mainland China.

Similarly, 485 has also become the representative of ID numbers in Hong Kong Special Administrative Region. This is because the last four digits of ID numbers in Hong Kong Special Administrative Region are sequential codes, and the number combination of 85 is relatively common, so in some occasions it is abbreviated as 485 to refer to ID numbers in Hong Kong Special Administrative Region.

In summary, the reason why the numbers 430 and 485 are used to refer to Mainland China and Hong Kong Special Administrative Region is that they have special significance and representation in their respective number systems. In practical use, people have also become accustomed to using these two numbers to distinguish different regions and identity information.