>>>>Types of problems like this fall into the category of cardinality. Some can't be solved without knowing the theory, since there is no "brute force" method. For example: You and your most significant other decide that for simplicity's sake you're only going to exchange 5 gifts, from a list of 52 (one for each week). Come Christmas morning, how many distinct possibilities (including opening order) are there?
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>>>You're right, I wouldn't want to try solving this without a knowledge of permutations...
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>>A bunch !!!!!
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>Did I express the problem wrong? It doesn't involve permutations, but rather distinct combinations. Perhaps I should have left the "opening order" business out.
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Ah, then we're back to combinations...