The CAS Registry Mumber 119490-80-1 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 1,1,9,4,9 and 0 respectively; the second part has 2 digits, 8 and 0 respectively. Calculate Digit Verification of CAS Registry Number 119490-80: (8*1)+(7*1)+(6*9)+(5*4)+(4*9)+(3*0)+(2*8)+(1*0)=141 141 % 10 = 1 So 119490-80-1 is a valid CAS Registry Number.