The CAS Registry Mumber 62020-22-8 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 6,2,0,2 and 0 respectively; the second part has 2 digits, 2 and 2 respectively. Calculate Digit Verification of CAS Registry Number 62020-22: (7*6)+(6*2)+(5*0)+(4*2)+(3*0)+(2*2)+(1*2)=68 68 % 10 = 8 So 62020-22-8 is a valid CAS Registry Number.