The CAS Registry Mumber 7030-64-0 includes 7 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 4 digits, 7,0,3 and 0 respectively; the second part has 2 digits, 6 and 4 respectively. Calculate Digit Verification of CAS Registry Number 7030-64: (6*7)+(5*0)+(4*3)+(3*0)+(2*6)+(1*4)=70 70 % 10 = 0 So 7030-64-0 is a valid CAS Registry Number.