The CAS Registry Mumber 13908-10-6 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 1,3,9,0 and 8 respectively; the second part has 2 digits, 1 and 0 respectively. Calculate Digit Verification of CAS Registry Number 13908-10: (7*1)+(6*3)+(5*9)+(4*0)+(3*8)+(2*1)+(1*0)=96 96 % 10 = 6 So 13908-10-6 is a valid CAS Registry Number.