The CAS Registry Mumber 95682-50-1 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 9,5,6,8 and 2 respectively; the second part has 2 digits, 5 and 0 respectively. Calculate Digit Verification of CAS Registry Number 95682-50: (7*9)+(6*5)+(5*6)+(4*8)+(3*2)+(2*5)+(1*0)=171 171 % 10 = 1 So 95682-50-1 is a valid CAS Registry Number.