The CAS Registry Mumber 94843-96-6 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 9,4,8,4 and 3 respectively; the second part has 2 digits, 9 and 6 respectively. Calculate Digit Verification of CAS Registry Number 94843-96: (7*9)+(6*4)+(5*8)+(4*4)+(3*3)+(2*9)+(1*6)=176 176 % 10 = 6 So 94843-96-6 is a valid CAS Registry Number.