The CAS Registry Mumber 76078-38-1 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 7,6,0,7 and 8 respectively; the second part has 2 digits, 3 and 8 respectively. Calculate Digit Verification of CAS Registry Number 76078-38: (7*7)+(6*6)+(5*0)+(4*7)+(3*8)+(2*3)+(1*8)=151 151 % 10 = 1 So 76078-38-1 is a valid CAS Registry Number.