The CAS Registry Mumber 130752-09-9 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 1,3,0,7,5 and 2 respectively; the second part has 2 digits, 0 and 9 respectively. Calculate Digit Verification of CAS Registry Number 130752-09: (8*1)+(7*3)+(6*0)+(5*7)+(4*5)+(3*2)+(2*0)+(1*9)=99 99 % 10 = 9 So 130752-09-9 is a valid CAS Registry Number.