The CAS Registry Mumber 151413-98-8 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 1,5,1,4,1 and 3 respectively; the second part has 2 digits, 9 and 8 respectively. Calculate Digit Verification of CAS Registry Number 151413-98: (8*1)+(7*5)+(6*1)+(5*4)+(4*1)+(3*3)+(2*9)+(1*8)=108 108 % 10 = 8 So 151413-98-8 is a valid CAS Registry Number.