The CAS Registry Mumber 94009-72-0 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 9,4,0,0 and 9 respectively; the second part has 2 digits, 7 and 2 respectively. Calculate Digit Verification of CAS Registry Number 94009-72: (7*9)+(6*4)+(5*0)+(4*0)+(3*9)+(2*7)+(1*2)=130 130 % 10 = 0 So 94009-72-0 is a valid CAS Registry Number.