The CAS Registry Mumber 118202-62-3 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 1,1,8,2,0 and 2 respectively; the second part has 2 digits, 6 and 2 respectively. Calculate Digit Verification of CAS Registry Number 118202-62: (8*1)+(7*1)+(6*8)+(5*2)+(4*0)+(3*2)+(2*6)+(1*2)=93 93 % 10 = 3 So 118202-62-3 is a valid CAS Registry Number.