The CAS Registry Mumber 85089-40-3 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 8,5,0,8 and 9 respectively; the second part has 2 digits, 4 and 0 respectively. Calculate Digit Verification of CAS Registry Number 85089-40: (7*8)+(6*5)+(5*0)+(4*8)+(3*9)+(2*4)+(1*0)=153 153 % 10 = 3 So 85089-40-3 is a valid CAS Registry Number.