The CAS Registry Mumber 90327-94-9 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 9,0,3,2 and 7 respectively; the second part has 2 digits, 9 and 4 respectively. Calculate Digit Verification of CAS Registry Number 90327-94: (7*9)+(6*0)+(5*3)+(4*2)+(3*7)+(2*9)+(1*4)=129 129 % 10 = 9 So 90327-94-9 is a valid CAS Registry Number.