The CAS Registry Mumber 115103-69-0 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 1,1,5,1,0 and 3 respectively; the second part has 2 digits, 6 and 9 respectively. Calculate Digit Verification of CAS Registry Number 115103-69: (8*1)+(7*1)+(6*5)+(5*1)+(4*0)+(3*3)+(2*6)+(1*9)=80 80 % 10 = 0 So 115103-69-0 is a valid CAS Registry Number.