WEBVTT

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Here is the problem: How many ways can you arrange 2 of 12 items in order?

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Permutations nPr (order matters).

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Use the permutation formula.

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Cancel 10! to leave the first 2 factors of 12!

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So the answer is P(12, 2) equals 132.

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There are 132 ordered arrangements of 2 items chosen from 12.

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Check: P(12, 2) equals C(12, 2) times 2! equals 66 times 2 equals 132.