Postnet codes Worksheet: Answers

zip + 4:
02123-4507     The check digit is: 6
98765-4321     The check digit is: 5
68506-2708     The check digit is: 8
48381-2307     The check digit is: 4 

zip + 4 + 2:
01234-5678-90  The check digit is: 5
28903-1234-78  The check digit is: 3
68002-1327-19  The check digit is: 1

error correction problems:
6702x-5804     x=9; the check digit is: 9
30412-710x     x=5; The check digit is: 7
58104-2x02     x=3; the check digit is: 5