The CAS Registry Mumber 33024-70-3 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 3,3,0,2 and 4 respectively; the second part has 2 digits, 7 and 0 respectively. Calculate Digit Verification of CAS Registry Number 33024-70: (7*3)+(6*3)+(5*0)+(4*2)+(3*4)+(2*7)+(1*0)=73 73 % 10 = 3 So 33024-70-3 is a valid CAS Registry Number.