The CAS Registry Mumber 1008472-78-3 includes 10 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 7 digits, 1,0,0,8,4,7 and 2 respectively; the second part has 2 digits, 7 and 8 respectively. Calculate Digit Verification of CAS Registry Number 1008472-78: (9*1)+(8*0)+(7*0)+(6*8)+(5*4)+(4*7)+(3*2)+(2*7)+(1*8)=133 133 % 10 = 3 So 1008472-78-3 is a valid CAS Registry Number.