Permutations & Combinations (nPr & nCr)

Find the total ways to arrange (Permutations) or select (Combinations) items from a set.

Inputs

Total items in set (n)

0100

Items chosen at a time (r)

0100

Combinations (nCr) - Selection

120

Permutations (nPr) - Arrangement

720

\displaystyle nCr = \frac{n!}{r!(n-r)!}, \quad nPr = \frac{n!}{(n-r)!}

Combinations (nCr) calculates select sets where order does not matter; Permutations (nPr) calculates arrangements where order is critical.