Check Digit
step 1: (8 + 1 + 2 + 0 + 0 + 1) x 3 = 12 x 3 = 36
step 2: 4 + 9 + 0 + 1 + 1 + 1 = 16
step 3: 36 + 16 = 52
step 4: 52 + X = 60
Therefore X = 8
The sum is divisible by 10.