The CAS Registry Mumber 94418-12-9 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 9,4,4,1 and 8 respectively; the second part has 2 digits, 1 and 2 respectively. Calculate Digit Verification of CAS Registry Number 94418-12: (7*9)+(6*4)+(5*4)+(4*1)+(3*8)+(2*1)+(1*2)=139 139 % 10 = 9 So 94418-12-9 is a valid CAS Registry Number.