The CAS Registry Mumber 314280-94-9 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 3,1,4,2,8 and 0 respectively; the second part has 2 digits, 9 and 4 respectively. Calculate Digit Verification of CAS Registry Number 314280-94: (8*3)+(7*1)+(6*4)+(5*2)+(4*8)+(3*0)+(2*9)+(1*4)=119 119 % 10 = 9 So 314280-94-9 is a valid CAS Registry Number.