The CAS Registry Mumber 39535-00-7 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 3,9,5,3 and 5 respectively; the second part has 2 digits, 0 and 0 respectively. Calculate Digit Verification of CAS Registry Number 39535-00: (7*3)+(6*9)+(5*5)+(4*3)+(3*5)+(2*0)+(1*0)=127 127 % 10 = 7 So 39535-00-7 is a valid CAS Registry Number.