The CAS Registry Mumber 5293-11-8 includes 7 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 4 digits, 5,2,9 and 3 respectively; the second part has 2 digits, 1 and 1 respectively. Calculate Digit Verification of CAS Registry Number 5293-11: (6*5)+(5*2)+(4*9)+(3*3)+(2*1)+(1*1)=88 88 % 10 = 8 So 5293-11-8 is a valid CAS Registry Number.