The CAS Registry Mumber 2882-49-7 includes 7 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 4 digits, 2,8,8 and 2 respectively; the second part has 2 digits, 4 and 9 respectively. Calculate Digit Verification of CAS Registry Number 2882-49: (6*2)+(5*8)+(4*8)+(3*2)+(2*4)+(1*9)=107 107 % 10 = 7 So 2882-49-7 is a valid CAS Registry Number.