The CAS Registry Mumber 112776-90-6 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 1,1,2,7,7 and 6 respectively; the second part has 2 digits, 9 and 0 respectively. Calculate Digit Verification of CAS Registry Number 112776-90: (8*1)+(7*1)+(6*2)+(5*7)+(4*7)+(3*6)+(2*9)+(1*0)=126 126 % 10 = 6 So 112776-90-6 is a valid CAS Registry Number.