The CAS Registry Mumber 679-08-3 includes 6 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 3 digits, 6,7 and 9 respectively; the second part has 2 digits, 0 and 8 respectively. Calculate Digit Verification of CAS Registry Number 679-08: (5*6)+(4*7)+(3*9)+(2*0)+(1*8)=93 93 % 10 = 3 So 679-08-3 is a valid CAS Registry Number.