The CAS Registry Mumber 96224-28-1 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 9,6,2,2 and 4 respectively; the second part has 2 digits, 2 and 8 respectively. Calculate Digit Verification of CAS Registry Number 96224-28: (7*9)+(6*6)+(5*2)+(4*2)+(3*4)+(2*2)+(1*8)=141 141 % 10 = 1 So 96224-28-1 is a valid CAS Registry Number.