The CAS Registry Mumber 82562-50-3 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 8,2,5,6 and 2 respectively; the second part has 2 digits, 5 and 0 respectively. Calculate Digit Verification of CAS Registry Number 82562-50: (7*8)+(6*2)+(5*5)+(4*6)+(3*2)+(2*5)+(1*0)=133 133 % 10 = 3 So 82562-50-3 is a valid CAS Registry Number.