The CAS Registry Mumber 8033-29-2 includes 7 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 4 digits, 8,0,3 and 3 respectively; the second part has 2 digits, 2 and 9 respectively. Calculate Digit Verification of CAS Registry Number 8033-29: (6*8)+(5*0)+(4*3)+(3*3)+(2*2)+(1*9)=82 82 % 10 = 2 So 8033-29-2 is a valid CAS Registry Number.