but your answer was not listed in Options: the options were A)9/8 B)2/3 C)8/9 D)2/9

frnd , is the answer is 9/8 ????

No sarika. Its 8/9. but dont know how!

BTW sarika Are you a Student? or a teacher?

well , here oxdn no. will be also in role

see 3FeO.Fe₂O₃   is given in the question , for feo fe oxdn state = 2 and for 3 such compd total is 3x2=6  , similar case with fe2o3 ,ie3   the total fe valency = 6+3=9  

now come to oxygen  here there are 4 oxy thus oxdn st = 4x2=8

 its turn of find formula for that ,

Fe    O

9        8   ( these are valency ie   now cross multiply them )

so u get the formula =  Fe8 O9  which also can be written as Fe8/9 O

hope this will serve ur purpose