The CAS Registry Mumber 93799-44-1 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 9,3,7,9 and 9 respectively; the second part has 2 digits, 4 and 4 respectively. Calculate Digit Verification of CAS Registry Number 93799-44: (7*9)+(6*3)+(5*7)+(4*9)+(3*9)+(2*4)+(1*4)=191 191 % 10 = 1 So 93799-44-1 is a valid CAS Registry Number.