The CAS Registry Mumber 96859-74-4 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 9,6,8,5 and 9 respectively; the second part has 2 digits, 7 and 4 respectively. Calculate Digit Verification of CAS Registry Number 96859-74: (7*9)+(6*6)+(5*8)+(4*5)+(3*9)+(2*7)+(1*4)=204 204 % 10 = 4 So 96859-74-4 is a valid CAS Registry Number.