The CAS Registry Mumber 927-22-0 includes 6 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 3 digits, 9,2 and 7 respectively; the second part has 2 digits, 2 and 2 respectively. Calculate Digit Verification of CAS Registry Number 927-22: (5*9)+(4*2)+(3*7)+(2*2)+(1*2)=80 80 % 10 = 0 So 927-22-0 is a valid CAS Registry Number.