The CAS Registry Mumber 150994-03-9 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 1,5,0,9,9 and 4 respectively; the second part has 2 digits, 0 and 3 respectively. Calculate Digit Verification of CAS Registry Number 150994-03: (8*1)+(7*5)+(6*0)+(5*9)+(4*9)+(3*4)+(2*0)+(1*3)=139 139 % 10 = 9 So 150994-03-9 is a valid CAS Registry Number.