The CAS Registry Mumber 103022-03-3 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 1,0,3,0,2 and 2 respectively; the second part has 2 digits, 0 and 3 respectively. Calculate Digit Verification of CAS Registry Number 103022-03: (8*1)+(7*0)+(6*3)+(5*0)+(4*2)+(3*2)+(2*0)+(1*3)=43 43 % 10 = 3 So 103022-03-3 is a valid CAS Registry Number.