The CAS Registry Mumber 92120-69-9 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 9,2,1,2 and 0 respectively; the second part has 2 digits, 6 and 9 respectively. Calculate Digit Verification of CAS Registry Number 92120-69: (7*9)+(6*2)+(5*1)+(4*2)+(3*0)+(2*6)+(1*9)=109 109 % 10 = 9 So 92120-69-9 is a valid CAS Registry Number.