The CAS Registry Mumber 112740-54-2 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 1,1,2,7,4 and 0 respectively; the second part has 2 digits, 5 and 4 respectively. Calculate Digit Verification of CAS Registry Number 112740-54: (8*1)+(7*1)+(6*2)+(5*7)+(4*4)+(3*0)+(2*5)+(1*4)=92 92 % 10 = 2 So 112740-54-2 is a valid CAS Registry Number.