The CAS Registry Mumber 10599-82-3 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 1,0,5,9 and 9 respectively; the second part has 2 digits, 8 and 2 respectively. Calculate Digit Verification of CAS Registry Number 10599-82: (7*1)+(6*0)+(5*5)+(4*9)+(3*9)+(2*8)+(1*2)=113 113 % 10 = 3 So 10599-82-3 is a valid CAS Registry Number.