The CAS Registry Mumber 98832-61-2 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 9,8,8,3 and 2 respectively; the second part has 2 digits, 6 and 1 respectively. Calculate Digit Verification of CAS Registry Number 98832-61: (7*9)+(6*8)+(5*8)+(4*3)+(3*2)+(2*6)+(1*1)=182 182 % 10 = 2 So 98832-61-2 is a valid CAS Registry Number.