The CAS Registry Mumber 101481-86-1 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 1,0,1,4,8 and 1 respectively; the second part has 2 digits, 8 and 6 respectively. Calculate Digit Verification of CAS Registry Number 101481-86: (8*1)+(7*0)+(6*1)+(5*4)+(4*8)+(3*1)+(2*8)+(1*6)=91 91 % 10 = 1 So 101481-86-1 is a valid CAS Registry Number.