Check Digit For 8 Digit Number

How to calculate a check digit in excel. The details to calculate this are as follows:

All variables in the calculation are positive integers.

We take each integer of the pro number and multiply it by a value and sum them to get a total.

An Example: 8 Digit Pro Number: 66988757
Pro Number: 6 6 9 8 8 7 5 7
Position in the Pro Number: 1 2 3 4 5 6 7 8
Multiply each digit in the pro number by (10-position) in the number, to achieve a sum.

Using our example pro again:
6*(10-1) + 6*(10-2) + 9*(10-3) + 8*(10-4) + 8*(10-5) + 7*(10-6) + 5*(10-7) + 7*(10-8)
6*9 + 6*8 + 9*7 + 8*6 + 8*5 + 7*4 + 5*3 + 7*2
54+ 48+ 63+48+40+28+15+14 = 310
Take the Sum of the previous calculation and divide it by 11
310/11 = 28

(Actually, it's 28.181818, but since we're working with integers, we truncate everything behind the decimal).

Figure a remainder by multiplying the quotient by 11 and subtracting from the sum.
Remainder = 310 - (28*11) ---> Remainder = 310 - 308 ----> Remainder = 2
Check Digit = 11- Remainder
Check Digit = 11 - 2 ---> Check Digit = 9
Note: if the check digit is 10 or 11, need to subtract 10 from the Check Digit.