The CAS Registry Mumber 97084-94-1 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 9,7,0,8 and 4 respectively; the second part has 2 digits, 9 and 4 respectively. Calculate Digit Verification of CAS Registry Number 97084-94: (7*9)+(6*7)+(5*0)+(4*8)+(3*4)+(2*9)+(1*4)=171 171 % 10 = 1 So 97084-94-1 is a valid CAS Registry Number.