The CAS Registry Mumber 118299-10-8 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 1,1,8,2,9 and 9 respectively; the second part has 2 digits, 1 and 0 respectively. Calculate Digit Verification of CAS Registry Number 118299-10: (8*1)+(7*1)+(6*8)+(5*2)+(4*9)+(3*9)+(2*1)+(1*0)=138 138 % 10 = 8 So 118299-10-8 is a valid CAS Registry Number.