WEBVTT

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Here is the problem: How many ways can you choose 2 items from 6?

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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(6, 2) equals 15.

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There are 15 ways to choose 2 items from 6 when order does not matter.

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Check: P(6, 2) equals C(6, 2) times 2! equals 15 times 2 equals 30.