The CAS Registry Mumber 89928-37-0 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 8,9,9,2 and 8 respectively; the second part has 2 digits, 3 and 7 respectively. Calculate Digit Verification of CAS Registry Number 89928-37: (7*8)+(6*9)+(5*9)+(4*2)+(3*8)+(2*3)+(1*7)=200 200 % 10 = 0 So 89928-37-0 is a valid CAS Registry Number.