Give an example of Problem Statement

You should understand here that you are looking for a statement of requirements, not a proposal for the solution. OOA specifies structure and behaviour of the object which comprise the requirements of that particular object. Different types of models are required to specify requirements of the objects. These object models compromise of the definition of objects in system, which includes: the object attributes, the object name, and the objects relationships with other objects. As we know, an object is a representation of a real-life entity, or an abstraction. For illustration, objects in a flight reservation system might contain: an airline flight, an airplane, an icon on a screen, or even a full screen with that a travel agent interacts.

State model describes the behaviour of objects in terms of states of the object and transitions allowed among objects, and the events which cause objects to change states. 

These models could be created and maintained with the help of CASE tools which support the representation of objects and object behaviour.

You can say that problem statement is a general report of the user's desires, difficulties , and its motive is to identify the general domain in that you will be working, and present some idea of why you are doing OOA.