- #1
aisha
- 584
- 0
For security, a credit card number is coded in the following way, so that it can be sent as a message. "Subtract each digit from 9"
code the credit card number 3201 2342 3458 0931
I don't understand the subtract each digit from 9 is that to code or uncode? Also for the above code the credit card what do I do to each number? do I add 9 or subtract 9?
I have another credit card number that is already coded, to find the original card number do i subtract each number from 9?
code the credit card number 3201 2342 3458 0931
I don't understand the subtract each digit from 9 is that to code or uncode? Also for the above code the credit card what do I do to each number? do I add 9 or subtract 9?
I have another credit card number that is already coded, to find the original card number do i subtract each number from 9?