The CAS Registry Mumber 82732-05-6 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 8,2,7,3 and 2 respectively; the second part has 2 digits, 0 and 5 respectively. Calculate Digit Verification of CAS Registry Number 82732-05: (7*8)+(6*2)+(5*7)+(4*3)+(3*2)+(2*0)+(1*5)=126 126 % 10 = 6 So 82732-05-6 is a valid CAS Registry Number.