The CAS Registry Mumber 83092-09-5 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 8,3,0,9 and 2 respectively; the second part has 2 digits, 0 and 9 respectively. Calculate Digit Verification of CAS Registry Number 83092-09: (7*8)+(6*3)+(5*0)+(4*9)+(3*2)+(2*0)+(1*9)=125 125 % 10 = 5 So 83092-09-5 is a valid CAS Registry Number.