The CAS Registry Mumber 883016-50-0 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 8,8,3,0,1 and 6 respectively; the second part has 2 digits, 5 and 0 respectively. Calculate Digit Verification of CAS Registry Number 883016-50: (8*8)+(7*8)+(6*3)+(5*0)+(4*1)+(3*6)+(2*5)+(1*0)=170 170 % 10 = 0 So 883016-50-0 is a valid CAS Registry Number.