when do use permutation and when do you use combination

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1

<p>i know you dont need it that much but im trying to get a 700 in math and any little thing will help just in case this problem pops up.</p>

2

<p>Permutation is when order matters.
(n!)/(n-r)!</p>

<p>Combination is when order does not matter.
(n!)/[(r)(n-r)!]</p>

<p>!=factorial for ex. 5! = 5 x 4 x 3 x 2 x 1</p>

<p>I'm guessing you know what n and r are.</p>

3

<p>Permutation is when the order matters.
Combination is just that... a combination of things when it doesn't matter what order they are in.</p>