The CAS Registry Mumber 650-29-3 includes 6 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 3 digits, 6,5 and 0 respectively; the second part has 2 digits, 2 and 9 respectively. Calculate Digit Verification of CAS Registry Number 650-29: (5*6)+(4*5)+(3*0)+(2*2)+(1*9)=63 63 % 10 = 3 So 650-29-3 is a valid CAS Registry Number.