The CAS Registry Mumber 1044757-55-2 includes 10 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 7 digits, 1,0,4,4,7,5 and 7 respectively; the second part has 2 digits, 5 and 5 respectively. Calculate Digit Verification of CAS Registry Number 1044757-55: (9*1)+(8*0)+(7*4)+(6*4)+(5*7)+(4*5)+(3*7)+(2*5)+(1*5)=152 152 % 10 = 2 So 1044757-55-2 is a valid CAS Registry Number.