The CAS Registry Mumber 97189-29-2 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 9,7,1,8 and 9 respectively; the second part has 2 digits, 2 and 9 respectively. Calculate Digit Verification of CAS Registry Number 97189-29: (7*9)+(6*7)+(5*1)+(4*8)+(3*9)+(2*2)+(1*9)=182 182 % 10 = 2 So 97189-29-2 is a valid CAS Registry Number.