The CAS Registry Mumber 36811-60-6 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 3,6,8,1 and 1 respectively; the second part has 2 digits, 6 and 0 respectively. Calculate Digit Verification of CAS Registry Number 36811-60: (7*3)+(6*6)+(5*8)+(4*1)+(3*1)+(2*6)+(1*0)=116 116 % 10 = 6 So 36811-60-6 is a valid CAS Registry Number.