The CAS Registry Mumber 32693-29-1 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 3,2,6,9 and 3 respectively; the second part has 2 digits, 2 and 9 respectively. Calculate Digit Verification of CAS Registry Number 32693-29: (7*3)+(6*2)+(5*6)+(4*9)+(3*3)+(2*2)+(1*9)=121 121 % 10 = 1 So 32693-29-1 is a valid CAS Registry Number.