The CAS Registry Mumber 93670-12-3 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 9,3,6,7 and 0 respectively; the second part has 2 digits, 1 and 2 respectively. Calculate Digit Verification of CAS Registry Number 93670-12: (7*9)+(6*3)+(5*6)+(4*7)+(3*0)+(2*1)+(1*2)=143 143 % 10 = 3 So 93670-12-3 is a valid CAS Registry Number.