The CAS Registry Mumber 86759-07-1 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 8,6,7,5 and 9 respectively; the second part has 2 digits, 0 and 7 respectively. Calculate Digit Verification of CAS Registry Number 86759-07: (7*8)+(6*6)+(5*7)+(4*5)+(3*9)+(2*0)+(1*7)=181 181 % 10 = 1 So 86759-07-1 is a valid CAS Registry Number.