The CAS Registry Mumber 137325-92-9 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 1,3,7,3,2 and 5 respectively; the second part has 2 digits, 9 and 2 respectively. Calculate Digit Verification of CAS Registry Number 137325-92: (8*1)+(7*3)+(6*7)+(5*3)+(4*2)+(3*5)+(2*9)+(1*2)=129 129 % 10 = 9 So 137325-92-9 is a valid CAS Registry Number.