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Unit: Counting, permutations, and combinations

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About this unit

How many outfits can you make from the shirts, pants, and socks in your closet? Address this question and more as you explore methods for counting how many possible outcomes there are in various situations. Learn about factorial, permutations, and combinations, and look at how to use these ideas to find probabilities.

Counting principle and factorial

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The counting principleGet 3 of 4 questions to level up!

Permutations

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PermutationsGet 3 of 4 questions to level up!

Combinations

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CombinationsGet 3 of 4 questions to level up!
Permutations & combinationsGet 5 of 7 questions to level up!

Combinatorics and probability

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

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Unit test

Level up on all the skills in this unit and collect up to 500 Mastery points!