The CAS Registry Mumber 93969-04-1 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 9,3,9,6 and 9 respectively; the second part has 2 digits, 0 and 4 respectively. Calculate Digit Verification of CAS Registry Number 93969-04: (7*9)+(6*3)+(5*9)+(4*6)+(3*9)+(2*0)+(1*4)=181 181 % 10 = 1 So 93969-04-1 is a valid CAS Registry Number.