The CAS Registry Mumber 50964-11-9 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 5,0,9,6 and 4 respectively; the second part has 2 digits, 1 and 1 respectively. Calculate Digit Verification of CAS Registry Number 50964-11: (7*5)+(6*0)+(5*9)+(4*6)+(3*4)+(2*1)+(1*1)=119 119 % 10 = 9 So 50964-11-9 is a valid CAS Registry Number.