The CAS Registry Mumber 792920-74-2 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 7,9,2,9,2 and 0 respectively; the second part has 2 digits, 7 and 4 respectively. Calculate Digit Verification of CAS Registry Number 792920-74: (8*7)+(7*9)+(6*2)+(5*9)+(4*2)+(3*0)+(2*7)+(1*4)=202 202 % 10 = 2 So 792920-74-2 is a valid CAS Registry Number.