The CAS Registry Mumber 107610-01-5 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 1,0,7,6,1 and 0 respectively; the second part has 2 digits, 0 and 1 respectively. Calculate Digit Verification of CAS Registry Number 107610-01: (8*1)+(7*0)+(6*7)+(5*6)+(4*1)+(3*0)+(2*0)+(1*1)=85 85 % 10 = 5 So 107610-01-5 is a valid CAS Registry Number.