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在線時間281 小時 最後登錄25-10-19 國民生產力22  附加生產力6293  貢獻生產力0  註冊時間04-11-19 閱讀權限10 帖子265 主題27 精華0 積分6580 UID35066 
 
  
 
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| Here is the formula of the checking number in your ID card, 
 Let the ID card no. be
 
 1st letter (X) - A,B,C,D,E,F, G ... etc
 2nd - 7th digit (N) -  N1,N2,N3,N4,N5,N6
 8 digit - inside (N7) ... the so called "checking number"
 
 In calculation, we put the 1st letter a value by rule as below
 A=1, B=2, C=3, etc
 
 Then, calculate a "T" value where
 T = 8*X + 7*N1 + 6*N2 + 5*N3 + 4*N4 + 3*N5 + 2*N1
 Divide T by 11, get the remainder, say R
 
 The checking number, N8 = 11 - R (the number inside bracket)
 If the calculated N8=10, it means A
 If the calculated N8=11, it means 0
 
 So, it is a Maths!  Not a bad spell or magic!
 
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