Determine the number of combinations possible when subsets of 𝑟 elements are selected from a set of 𝑛 elements without regard to order.
Example Problems
How many unique ways are there to arrange the letters in the word BALLOON?
How many unique ways are there to arrange the letters in the word COMMITTEE?
How many numbers between 1 and 100 (inclusive) are divisible by 4 or 5?
Khan Academy ResourcesCombinationsProbability with permutations and combinationsCombination example: 9 card handsExample: Lottery probabilityMega millions jackpot probabilityCombination formulaProbability with permutations & combinations example: taste testingPossible three letter wordsProbability with combinations example: choosing cardsIntro to combinations
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