The CAS Registry Mumber 130948-29-7 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 1,3,0,9,4 and 8 respectively; the second part has 2 digits, 2 and 9 respectively. Calculate Digit Verification of CAS Registry Number 130948-29: (8*1)+(7*3)+(6*0)+(5*9)+(4*4)+(3*8)+(2*2)+(1*9)=127 127 % 10 = 7 So 130948-29-7 is a valid CAS Registry Number.