The CAS Registry Mumber 12024-41-8 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 1,2,0,2 and 4 respectively; the second part has 2 digits, 4 and 1 respectively. Calculate Digit Verification of CAS Registry Number 12024-41: (7*1)+(6*2)+(5*0)+(4*2)+(3*4)+(2*4)+(1*1)=48 48 % 10 = 8 So 12024-41-8 is a valid CAS Registry Number.