Complementary counting

Revision as of 16:51, 10 August 2010 by Mathgeek2006 (talk | contribs) (Introductory)

Complementary counting is counting the complement of the set we want to count, and subtracting that from the total number of possibilities, or the universal set for that particular problem. A big hint that complementary counting may lead to a quick solution is the phrase "at least".



See also

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