The CAS Registry Mumber 8073-08-3 includes 7 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 4 digits, 8,0,7 and 3 respectively; the second part has 2 digits, 0 and 8 respectively. Calculate Digit Verification of CAS Registry Number 8073-08: (6*8)+(5*0)+(4*7)+(3*3)+(2*0)+(1*8)=93 93 % 10 = 3 So 8073-08-3 is a valid CAS Registry Number.