The CAS Registry Mumber 93488-25-6 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 9,3,4,8 and 8 respectively; the second part has 2 digits, 2 and 5 respectively. Calculate Digit Verification of CAS Registry Number 93488-25: (7*9)+(6*3)+(5*4)+(4*8)+(3*8)+(2*2)+(1*5)=166 166 % 10 = 6 So 93488-25-6 is a valid CAS Registry Number.