The Question: A marketing agency conducted a survey of 5000 people. The same list of 5 current television programs was presented to each person, who was then asked to state which of those programs he or she regularly watched. In analyzing the results, the agency defined an equivalence relation R on the set of 5000 people as follows: for any people x and y,
xRy <-> x regularly watches exactly the smae programs in the list as y does.
How many different equivalence classes can there be for this equivalence relation? Why?
now my question: how do you go about determining the number of equivalence classes (for any problem).
Thank-you in advance