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Unit: Counting, permutations, and combinations

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Possible mastery points

Counting principle and factorial

Learn
Count outcomes using tree diagram
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Counting outcomes: flower pots
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Practice
The counting principleGet 3 of 4 questions to level up!

Permutations

Learn
Permutation formula
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Zero factorial or 0!
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Factorial and counting seat arrangements
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Possible three letter words
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Ways to arrange colors
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Ways to pick officers
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Practice
PermutationsGet 3 of 4 questions to level up!

Combinations

Learn
Intro to combinations
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Combination formula
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Handshaking combinations
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Combination example: 9 card hands
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Practice
CombinationsGet 3 of 4 questions to level up!
Permutations & combinationsGet 5 of 7 questions to level up!

Combinatorics and probability

Learn
Probability using combinations
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Probability & combinations (2 of 2)
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Example: Different ways to pick officers
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Example: Combinatorics and probability
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Getting exactly two heads (combinatorics)
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Exactly three heads in five flips
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Generalizing with binomial coefficients (bit advanced)
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Example: Lottery probability
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Conditional probability and combinations
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Mega millions jackpot probability
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Birthday probability problem
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Practice
Probability with permutations and combinationsGet 3 of 4 questions to level up!
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About this unit

This unit covers methods for counting how many possible outcomes there are in various situations. We'll learn about factorial, permutations, and combinations. We'll also look at how to use these ideas to find probabilities.