The CAS Registry Mumber 75473-52-8 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 7,5,4,7 and 3 respectively; the second part has 2 digits, 5 and 2 respectively. Calculate Digit Verification of CAS Registry Number 75473-52: (7*7)+(6*5)+(5*4)+(4*7)+(3*3)+(2*5)+(1*2)=148 148 % 10 = 8 So 75473-52-8 is a valid CAS Registry Number.