The CAS Registry Mumber 40018-12-0 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 4,0,0,1 and 8 respectively; the second part has 2 digits, 1 and 2 respectively. Calculate Digit Verification of CAS Registry Number 40018-12: (7*4)+(6*0)+(5*0)+(4*1)+(3*8)+(2*1)+(1*2)=60 60 % 10 = 0 So 40018-12-0 is a valid CAS Registry Number.