Scan Line: 20801640112000000215783910000201806111990000001300
Positions 10 – 36: 120000002157839100002018061
Right most position and every other position:
1, 0, 1, 2, 0, 0, 9, 8, 5, 2, 0, 0, 0, 1
Multiply by 2: 2, 0, 2, 4, 0, 0, 18, 16, 10, 4, 0, 0, 0, 2
Digits not multiplied (from right to left): 6, 8, 0, 0, 0, 1, 3, 7, 1, 0, 0, 0, 2
Add the digits:
1st number {2+0+2+4+0+0+(1+8)+(1+6)+(1+0)+4+0+0+0+2} = 31
2nd number {6+8+0+0+0+1+3+7+1+0+0+0+2} = 28
Sum = 59
Next highest multiple of 10 = 60
Subtract 60 – 59 = 1
Check digit = 1