The CAS Registry Mumber 147290-71-9 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 1,4,7,2,9 and 0 respectively; the second part has 2 digits, 7 and 1 respectively. Calculate Digit Verification of CAS Registry Number 147290-71: (8*1)+(7*4)+(6*7)+(5*2)+(4*9)+(3*0)+(2*7)+(1*1)=139 139 % 10 = 9 So 147290-71-9 is a valid CAS Registry Number.