Permutations Formula

로도 알려져 있음: nPr Formula, Arrangement Formula

P(n, r) = \frac{n!}{(n-r)!}

P(n,r) = n! / (n-r)!

계산 내용

Counts the number of ways to arrange r items from a set of n, where ORDER MATTERS.

상징	이름	단위	설명
n	Total Items	—	Total number of items to choose from
r	Items Chosen	—	Number of items being arranged

1P(5,3) = 5! / (5-3)! = 5! / 2!

2= 120 / 2 = 60

결과: 60

Permutations = order matters. Combinations = order doesn't matter.