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Sodium
Dec 13, 2008, 11:52 PM
So I was bored. And I was wondering...
How many possible combinations could you make of the numbers

1, 2, 3, 4

Like numbers like, 1234, 4321, 3241

I'm curious

Clough
Dec 14, 2008, 01:20 AM
Hi, Sodium!

I found what is quoted below on the following site and thought that it was kind of cool!

See How Many Number Combinations You Can Make - WebMath (http://www.webmath.com/k8perm.html)


You want to see all possible permutations of these items:
1, 2, 3, 4

There are 24 possible permutations for these 4 items.

For n items, there are n! (n factorial) ways of arranging them, when the order of your arrangements matters.

n!=n × (n-1) × (n-2) ×... 1. Here 4!=4 × 3 × 2 × 1 = 24.

Here are the possible permutations:
1: 1 2 3 4
2: 1 2 4 3
3: 1 3 2 4
4: 1 4 2 3
5: 1 3 4 2
6: 1 4 3 2
7: 2 1 3 4
8: 2 1 4 3
9: 3 1 2 4
10: 4 1 2 3
11: 3 1 4 2
12: 4 1 3 2
13: 2 3 1 4
14: 2 4 1 3
15: 3 2 1 4
16: 4 2 1 3
17: 3 4 1 2
18: 4 3 1 2
19: 2 3 4 1
20: 2 4 3 1
21: 3 2 4 1
22: 4 2 3 1
23: 3 4 2 1
24: 4 3 2 1

ROLCAM
Dec 14, 2008, 02:36 AM
First determine the first six from the number 1 figure.
Then multiply by 4

You get 6 times 4 = ANSWER 24 possibillities.

rolcam

Clough
Dec 17, 2008, 10:46 PM
I'm no whiz at math, but I think that the posters above coming up with the mathematical ways to figure out the problem are great! :)

asterisk_man
Dec 18, 2008, 09:25 AM
You're talking about permutations (http://en.wikipedia.org/wiki/Permutation). N items can be arranged in n! Ways (where ! Is the symbol for factorial (http://en.wikipedia.org/wiki/Factorial)).
For example, 5 items can be arranged in 120 ways and 20 items can be arranged in 2,432,902,008,176,640,000 ways.