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# Counting, permutations, and combinations

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Count outcomes using tree diagramCounting outcomes: flower pots

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The counting principleGet 3 of 4 questions to level up!

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Permutation formulaZero factorial or 0!Factorial and counting seat arrangementsPossible three letter wordsWays to arrange colorsWays to pick officers

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PermutationsGet 3 of 4 questions to level up!

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Intro to combinationsCombination formulaHandshaking combinationsCombination example: 9 card hands

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CombinationsGet 3 of 4 questions to level up!

Permutations & combinationsGet 5 of 7 questions to level up!

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Probability using combinationsProbability & combinations (2 of 2)Example: Different ways to pick officersExample: Combinatorics and probabilityGetting exactly two heads (combinatorics)Exactly three heads in five flipsGeneralizing with binomial coefficients (bit advanced)Example: Lottery probabilityConditional probability and combinationsMega millions jackpot probabilityBirthday probability problem

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Probability with permutations and combinationsGet 3 of 4 questions to level up!