My math skills are deficient.
I've tried to work with 4 different formulas provided for other check-digit
makers, but my source number is 8 digits, and while it's a simpler formula, I
can't figure it out based on the other formulas:
Step 1 - divide the 8-digit number by 7;
Step 2 - multiply the remainder by 7. (If the remainder is more than one
digit, use only the first digit;
Step 3, Round that answer up to the next whole number. This is the check
digit

Note: If the remainder is zero, it is a whole number. Do not round up.
Zero is the check-digit.

Any help ???
Thanks in advance ...