The CAS Registry Mumber 4402-92-0 includes 7 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 4 digits, 4,4,0 and 2 respectively; the second part has 2 digits, 9 and 2 respectively. Calculate Digit Verification of CAS Registry Number 4402-92: (6*4)+(5*4)+(4*0)+(3*2)+(2*9)+(1*2)=70 70 % 10 = 0 So 4402-92-0 is a valid CAS Registry Number.