The CAS Registry Mumber 113473-47-5 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 1,1,3,4,7 and 3 respectively; the second part has 2 digits, 4 and 7 respectively. Calculate Digit Verification of CAS Registry Number 113473-47: (8*1)+(7*1)+(6*3)+(5*4)+(4*7)+(3*3)+(2*4)+(1*7)=105 105 % 10 = 5 So 113473-47-5 is a valid CAS Registry Number.