Definition of “Problem”
Using Lester’s definition (Lester, 1978; Lester, 1980): a problem is a situation in which an individual or a group is called upon to perform a task for which there is no readily accessible algorithm which determines completely the method of solution. At the other extreme, Collin’s Dictionary (1993) defines a problem as a statement requiring a solution usually by means of several operations or constructions. Here, to highlight a problem as one where “there is no readily accessible algorithm”, we shall call it non-routine problem. Other “routine” problems are simply referred to as “questions” or loosely “routine problem” for our discussion.