WEBVTT

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Here is the problem: How many ways can you arrange 4 of 10 items in order?

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Permutations nPr (order matters).

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Use the permutation formula.

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Cancel 6! to leave the first 4 factors of 10!

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So the answer is P(10, 4) equals 5,040.

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There are 5,040 ordered arrangements of 4 items chosen from 10.

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Check: P(10, 4) equals C(10, 4) times 4! equals 210 times 24 equals 5,040.