The CAS Registry Mumber 24182-44-3 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 2,4,1,8 and 2 respectively; the second part has 2 digits, 4 and 4 respectively. Calculate Digit Verification of CAS Registry Number 24182-44: (7*2)+(6*4)+(5*1)+(4*8)+(3*2)+(2*4)+(1*4)=93 93 % 10 = 3 So 24182-44-3 is a valid CAS Registry Number.