The CAS Registry Mumber 122842-92-6 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 1,2,2,8,4 and 2 respectively; the second part has 2 digits, 9 and 2 respectively. Calculate Digit Verification of CAS Registry Number 122842-92: (8*1)+(7*2)+(6*2)+(5*8)+(4*4)+(3*2)+(2*9)+(1*2)=116 116 % 10 = 6 So 122842-92-6 is a valid CAS Registry Number.