The CAS Registry Mumber 8024-00-8 includes 7 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 4 digits, 8,0,2 and 4 respectively; the second part has 2 digits, 0 and 0 respectively. Calculate Digit Verification of CAS Registry Number 8024-00: (6*8)+(5*0)+(4*2)+(3*4)+(2*0)+(1*0)=68 68 % 10 = 8 So 8024-00-8 is a valid CAS Registry Number.