The CAS Registry Mumber 1256579-48-2 includes 10 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 7 digits, 1,2,5,6,5,7 and 9 respectively; the second part has 2 digits, 4 and 8 respectively. Calculate Digit Verification of CAS Registry Number 1256579-48: (9*1)+(8*2)+(7*5)+(6*6)+(5*5)+(4*7)+(3*9)+(2*4)+(1*8)=192 192 % 10 = 2 So 1256579-48-2 is a valid CAS Registry Number.