Hey math/statistics wizards

[85Sooner]

What is the formula for finding our the number of possible outcomes given a certain number of variables.

Ie:



Variables 1,2,3

answer 4
12
23
13
123

[Ike]

ummm, you need to give more information.

in other words are you asking what are the number of possible ways to take n things some number of times?

because in the example you give, you leave out 3 possible outcomes:
1
2
3

anyway, these are called combinations when the order doesn't matter, and the formula for the number of combinations of n objects taken r at a time is:

C_n,r=n!/(r!*(n-r)!)

If the order does matter, then you are asking for permutations, in which case the number of permutations of n objects taken r at a time is equal to:

nPr=n!/(n-r)!


<edit> so, based on your example, you have asked then "how many combinations of the numbers 1, 2, and 3 exist that contain more than one number, for which the answer would be

C_3,2 + C_3,3 = 3!/(2!*1!) + 3!/3! = 3+1

[Widescreen]

And while we're at it, how many licks does it take to get to the center of a Tootsie Roll Toosie Pop?

[OUinFLA]

oh, oh, oh.........
how many posts on SO does it take to make you realize you waste a lot of time on the internet?

[Widescreen]

6,827

[SCOUT]

ummm, you need to give more information.

in other words are you asking what are the number of possible ways to take n things some number of times?

because in the example you give, you leave out 3 possible outcomes:
1
2
3

anyway, these are called combinations when the order doesn't matter, and the formula for the number of combinations of n objects taken r at a time is:

C_n,r=n!/(r!*(n-r)!)

If the order does matter, then you are asking for permutations, in which case the number of permutations of n objects taken r at a time is equal to:

nPr=n!/(n-r)!


<edit> so, based on your example, you have asked then "how many combinations of the numbers 1, 2, and 3 exist that contain more than one number, for which the answer would be

C_3,2 + C_3,3 = 3!/(2!*1!) + 3!/3! = 3+1


Yeah, that is pretty much what I was going to say.:cool:

[BlondeSoonerGirl]

Math is hard.

[JohnnyMack]

Who's Math?

[Hamhock]

ummm, you need to give more information.

in other words are you asking what are the number of possible ways to take n things some number of times?

because in the example you give, you leave out 3 possible outcomes:
1
2
3

anyway, these are called combinations when the order doesn't matter, and the formula for the number of combinations of n objects taken r at a time is:

C_n,r=n!/(r!*(n-r)!)

If the order does matter, then you are asking for permutations, in which case the number of permutations of n objects taken r at a time is equal to:

nPr=n!/(n-r)!


<edit> so, based on your example, you have asked then "how many combinations of the numbers 1, 2, and 3 exist that contain more than one number, for which the answer would be

C_3,2 + C_3,3 = 3!/(2!*1!) + 3!/3! = 3+1


I was gonna say: Nerd!!

[Oldnslo]

What happened to N (squared)?

I both read and didn't understand Ike's reply. I just have a vague and distant memory of the formula.

[85Sooner]

Thank you, now that rings a bell!

[OCUDad]

I both read and didn't understand Ike's reply.Funny -- neither did Ike. :D