The CAS Registry Mumber 8070-76-6 includes 7 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 4 digits, 8,0,7 and 0 respectively; the second part has 2 digits, 7 and 6 respectively. Calculate Digit Verification of CAS Registry Number 8070-76: (6*8)+(5*0)+(4*7)+(3*0)+(2*7)+(1*6)=96 96 % 10 = 6 So 8070-76-6 is a valid CAS Registry Number.