Math 108 Topics in Mathematics | Laura Barnes |
16.1 Check Digits U.S. Postal Service Money Order - Video
16.1 Check Digits U.S. Postal Service Money Order - Video
Key Ideas
Many frequently used types of error-detecting codes for identification numbers include an extra digit
(usually the last digit) called a check digit. The check digit can be compared to the rest of the number to check for validity.
For a U.S. Postal Service money order, the check digit (the last digit) is the remainder you get when you divide the sum of the other digits by 9.