The CAS Registry Mumber 3082-84-6 includes 7 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 4 digits, 3,0,8 and 2 respectively; the second part has 2 digits, 8 and 4 respectively. Calculate Digit Verification of CAS Registry Number 3082-84: (6*3)+(5*0)+(4*8)+(3*2)+(2*8)+(1*4)=76 76 % 10 = 6 So 3082-84-6 is a valid CAS Registry Number.