The CAS Registry Mumber 6483-60-9 includes 7 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 4 digits, 6,4,8 and 3 respectively; the second part has 2 digits, 6 and 0 respectively. Calculate Digit Verification of CAS Registry Number 6483-60: (6*6)+(5*4)+(4*8)+(3*3)+(2*6)+(1*0)=109 109 % 10 = 9 So 6483-60-9 is a valid CAS Registry Number.