The CAS Registry Mumber 76893-37-3 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 7,6,8,9 and 3 respectively; the second part has 2 digits, 3 and 7 respectively. Calculate Digit Verification of CAS Registry Number 76893-37: (7*7)+(6*6)+(5*8)+(4*9)+(3*3)+(2*3)+(1*7)=183 183 % 10 = 3 So 76893-37-3 is a valid CAS Registry Number.