The CAS Registry Mumber 65054-22-0 includes 8 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 5 digits, 6,5,0,5 and 4 respectively; the second part has 2 digits, 2 and 2 respectively. Calculate Digit Verification of CAS Registry Number 65054-22: (7*6)+(6*5)+(5*0)+(4*5)+(3*4)+(2*2)+(1*2)=110 110 % 10 = 0 So 65054-22-0 is a valid CAS Registry Number.