The CAS Registry Mumber 105149-92-6 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 1,0,5,1,4 and 9 respectively; the second part has 2 digits, 9 and 2 respectively. Calculate Digit Verification of CAS Registry Number 105149-92: (8*1)+(7*0)+(6*5)+(5*1)+(4*4)+(3*9)+(2*9)+(1*2)=106 106 % 10 = 6 So 105149-92-6 is a valid CAS Registry Number.