The CAS Registry Mumber 914359-78-7 includes 9 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 6 digits, 9,1,4,3,5 and 9 respectively; the second part has 2 digits, 7 and 8 respectively. Calculate Digit Verification of CAS Registry Number 914359-78: (8*9)+(7*1)+(6*4)+(5*3)+(4*5)+(3*9)+(2*7)+(1*8)=187 187 % 10 = 7 So 914359-78-7 is a valid CAS Registry Number.