WEBVTT

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Here is the problem: How many ways can you choose 4 items from 20?

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Combinations nCr (order does not matter).

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Use the combination formula.

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Divide the permutations by r! because order does not matter.

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So the answer is C(20, 4) equals 4,845.

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There are 4,845 ways to choose 4 items from 20 when order does not matter.

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Check: P(20, 4) equals C(20, 4) times 4! equals 4,845 times 24 equals 116,280.