The CAS Registry Mumber 42960-09-8 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 4,2,9,6 and 0 respectively; the second part has 2 digits, 0 and 9 respectively. Calculate Digit Verification of CAS Registry Number 42960-09: (7*4)+(6*2)+(5*9)+(4*6)+(3*0)+(2*0)+(1*9)=118 118 % 10 = 8 So 42960-09-8 is a valid CAS Registry Number.