The CAS Registry Mumber 110259-10-4 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 1,1,0,2,5 and 9 respectively; the second part has 2 digits, 1 and 0 respectively. Calculate Digit Verification of CAS Registry Number 110259-10: (8*1)+(7*1)+(6*0)+(5*2)+(4*5)+(3*9)+(2*1)+(1*0)=74 74 % 10 = 4 So 110259-10-4 is a valid CAS Registry Number.