The CAS Registry Mumber 64830-95-1 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 6,4,8,3 and 0 respectively; the second part has 2 digits, 9 and 5 respectively. Calculate Digit Verification of CAS Registry Number 64830-95: (7*6)+(6*4)+(5*8)+(4*3)+(3*0)+(2*9)+(1*5)=141 141 % 10 = 1 So 64830-95-1 is a valid CAS Registry Number.