The CAS Registry Mumber 117730-46-8 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 1,1,7,7,3 and 0 respectively; the second part has 2 digits, 4 and 6 respectively. Calculate Digit Verification of CAS Registry Number 117730-46: (8*1)+(7*1)+(6*7)+(5*7)+(4*3)+(3*0)+(2*4)+(1*6)=118 118 % 10 = 8 So 117730-46-8 is a valid CAS Registry Number.