The CAS Registry Mumber 93561-95-6 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 9,3,5,6 and 1 respectively; the second part has 2 digits, 9 and 5 respectively. Calculate Digit Verification of CAS Registry Number 93561-95: (7*9)+(6*3)+(5*5)+(4*6)+(3*1)+(2*9)+(1*5)=156 156 % 10 = 6 So 93561-95-6 is a valid CAS Registry Number.