The CAS Registry Mumber 3069-51-0 includes 7 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 4 digits, 3,0,6 and 9 respectively; the second part has 2 digits, 5 and 1 respectively. Calculate Digit Verification of CAS Registry Number 3069-51: (6*3)+(5*0)+(4*6)+(3*9)+(2*5)+(1*1)=80 80 % 10 = 0 So 3069-51-0 is a valid CAS Registry Number.