The CAS Registry Mumber 74483-12-8 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 7,4,4,8 and 3 respectively; the second part has 2 digits, 1 and 2 respectively. Calculate Digit Verification of CAS Registry Number 74483-12: (7*7)+(6*4)+(5*4)+(4*8)+(3*3)+(2*1)+(1*2)=138 138 % 10 = 8 So 74483-12-8 is a valid CAS Registry Number.