The CAS Registry Mumber 888483-98-5 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 8,8,8,4,8 and 3 respectively; the second part has 2 digits, 9 and 8 respectively. Calculate Digit Verification of CAS Registry Number 888483-98: (8*8)+(7*8)+(6*8)+(5*4)+(4*8)+(3*3)+(2*9)+(1*8)=255 255 % 10 = 5 So 888483-98-5 is a valid CAS Registry Number.