The CAS Registry Mumber 102794-17-2 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 1,0,2,7,9 and 4 respectively; the second part has 2 digits, 1 and 7 respectively. Calculate Digit Verification of CAS Registry Number 102794-17: (8*1)+(7*0)+(6*2)+(5*7)+(4*9)+(3*4)+(2*1)+(1*7)=112 112 % 10 = 2 So 102794-17-2 is a valid CAS Registry Number.