The CAS Registry Mumber 376-44-3 includes 6 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 3 digits, 3,7 and 6 respectively; the second part has 2 digits, 4 and 4 respectively. Calculate Digit Verification of CAS Registry Number 376-44: (5*3)+(4*7)+(3*6)+(2*4)+(1*4)=73 73 % 10 = 3 So 376-44-3 is a valid CAS Registry Number.