The CAS Registry Mumber 85422-46-4 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 8,5,4,2 and 2 respectively; the second part has 2 digits, 4 and 6 respectively. Calculate Digit Verification of CAS Registry Number 85422-46: (7*8)+(6*5)+(5*4)+(4*2)+(3*2)+(2*4)+(1*6)=134 134 % 10 = 4 So 85422-46-4 is a valid CAS Registry Number.