The CAS Registry Mumber 113237-22-2 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 1,1,3,2,3 and 7 respectively; the second part has 2 digits, 2 and 2 respectively. Calculate Digit Verification of CAS Registry Number 113237-22: (8*1)+(7*1)+(6*3)+(5*2)+(4*3)+(3*7)+(2*2)+(1*2)=82 82 % 10 = 2 So 113237-22-2 is a valid CAS Registry Number.