WEBVTT

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Here is the problem: How many ways can you choose 7 items from 15?

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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(15, 7) equals 6,435.

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There are 6,435 ways to choose 7 items from 15 when order does not matter.

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Check: P(15, 7) equals C(15, 7) times 7! equals 6,435 times 5,040 equals 32,432,400.