 Intro to Combinations and Permutations
 Permutations with Repetition
 Permutations without Repetition
 Permutations Formula

License Plates  Android Lock Screen
 Tigers and Bears  Oh My

Combination without Repetition  Combination Formula
 Combining Combinations

The String of Beads  Anagrams
 Combinations with Repetition I
 Combinations with Repetition II
Permutations without Repetition
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Permutations with repetition was a simple formula: NxN... or N^{E.} But what happens if you cannot reuse any elements? For example, let's say only 3 students entered the poetry contest you are judging. How many possible ways are there to award 1^{st}, 2^{nd} and 3^{rd} place?
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Challenge
The ForceBall Lottery uses 12 balls numbered 112. Each ball spins in a machine until it pops out. How many possible orders are there (for the balls to pop out) in the ForceBall Lottery?
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Comments
rodrigo perez
Sep 28, 5:53 PMWhat's gamma(13)?
Ian Rainford
Nov 15, 6:44 PM12 factorial
nubxaker
Nov 21, 8:13 PMNice!