The CAS Registry Mumber 1195-15-9 includes 7 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 4 digits, 1,1,9 and 5 respectively; the second part has 2 digits, 1 and 5 respectively. Calculate Digit Verification of CAS Registry Number 1195-15: (6*1)+(5*1)+(4*9)+(3*5)+(2*1)+(1*5)=69 69 % 10 = 9 So 1195-15-9 is a valid CAS Registry Number.