The CAS Registry Mumber 3262-71-3 includes 7 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 4 digits, 3,2,6 and 2 respectively; the second part has 2 digits, 7 and 1 respectively. Calculate Digit Verification of CAS Registry Number 3262-71: (6*3)+(5*2)+(4*6)+(3*2)+(2*7)+(1*1)=73 73 % 10 = 3 So 3262-71-3 is a valid CAS Registry Number.