The CAS Registry Mumber 39192-25-1 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 3,9,1,9 and 2 respectively; the second part has 2 digits, 2 and 5 respectively. Calculate Digit Verification of CAS Registry Number 39192-25: (7*3)+(6*9)+(5*1)+(4*9)+(3*2)+(2*2)+(1*5)=131 131 % 10 = 1 So 39192-25-1 is a valid CAS Registry Number.