The CAS Registry Mumber 934736-45-5 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 9,3,4,7,3 and 6 respectively; the second part has 2 digits, 4 and 5 respectively. Calculate Digit Verification of CAS Registry Number 934736-45: (8*9)+(7*3)+(6*4)+(5*7)+(4*3)+(3*6)+(2*4)+(1*5)=195 195 % 10 = 5 So 934736-45-5 is a valid CAS Registry Number.