Inventory is a synonym of Account. Account is related to Expense. Expense is related to Price. Price is a type of Worth. 
City is related to Sex. Sex is related to Man. Man is related to Policeman. Inspector is a type of Policeman. 
Inventory <--Synonym--> Account <--RelatedTo--> Expense <--RelatedTo--> Price --IsA--> Worth 
City <--RelatedTo--> Sex <--RelatedTo--> Man <--RelatedTo--> Policeman <--IsA-- Inspector 