The CAS Registry Mumber 94147-89-4 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 9,4,1,4 and 7 respectively; the second part has 2 digits, 8 and 9 respectively. Calculate Digit Verification of CAS Registry Number 94147-89: (7*9)+(6*4)+(5*1)+(4*4)+(3*7)+(2*8)+(1*9)=154 154 % 10 = 4 So 94147-89-4 is a valid CAS Registry Number.