The CAS Registry Mumber 79479-83-7 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 7,9,4,7 and 9 respectively; the second part has 2 digits, 8 and 3 respectively. Calculate Digit Verification of CAS Registry Number 79479-83: (7*7)+(6*9)+(5*4)+(4*7)+(3*9)+(2*8)+(1*3)=197 197 % 10 = 7 So 79479-83-7 is a valid CAS Registry Number.