The CAS Registry Mumber 5194-48-9 includes 7 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 4 digits, 5,1,9 and 4 respectively; the second part has 2 digits, 4 and 8 respectively. Calculate Digit Verification of CAS Registry Number 5194-48: (6*5)+(5*1)+(4*9)+(3*4)+(2*4)+(1*8)=99 99 % 10 = 9 So 5194-48-9 is a valid CAS Registry Number.