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jumpergirl

Math Help!

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               n!

n_C_k = ----------
k!(n - k)!


n = number of things
k = number choosen

So I'd add 5C0 + 5C1 + 5C2 + ...

edit in case you forgot, ! means 'factorial' so 5! = 5*4*3*2*1

WAG, 37 or 42... I think.
it's like incest - you're substituting convenience for quality

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What is the formula for figuring how many possible combinations are available?

I have a model home with 5 options. You can chose and combination you want (from no options to all 5). How do I determine how many possible combinations I can have?

Thanks! :)



2 raised to the 5th = 32 combinations, including a null option of none of them (as long as the options are completely independent and only yes/no type of option)

Each option is yes/no - only 2 choices
so 2 options is 2x2
3 options is (2x2)x2 (add the 3rd option)
and so on

...
Driving is a one dimensional activity - a monkey can do it - being proud of your driving abilities is like being proud of being able to put on pants

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What is the formula for figuring how many possible combinations are available?

I have a model home with 5 options. You can chose and combination you want (from no options to all 5). How do I determine how many possible combinations I can have?

Thanks! :)



2 raised to the 5th = 32 combinations, including a null option of none of them (as long as the options are completely independent and only yes/no type of option)

Each option is yes/no - only 2 choices
so 2 options is 2x2
3 options is (2x2)x2 (add the 3rd option)
and so on



We have a winner!

For Great Deals on Gear


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What is the formula for figuring how many possible combinations are available?

I have a model home with 5 options. You can chose and combination you want (from no options to all 5). How do I determine how many possible combinations I can have?

Thanks! :)



Ok. Here's the deal. When you are talking taking some number of objects from a group without regard to order, that is called a combination.

What you have a group of five options, but you can choose any number of them or none at all.

Lets's say you choose none of the options, there is only 1 way to do that.

If you take only one option, there are 5 choices.

If you take two options, there are 10 ways to do that.

and so on.

It all adds up to 1 + 5 + 10 + 10 + 5 + 1 = 32

Walt

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If you can count in binary, it might make it easier to understand why your solution is 2^5 (2*2*2*2*2);)
Think of 0=option not required and 1=Option required. Then assign each of the options into a column.
Therefore...
00000 (no options)
00001 (only option assigned to column 5 is required)
00010
00011
00100
00101
00110
00111 (options 3, 4 and 5 required etc., etc.)
01000
01001
01010
01011
01100
01101
01110
01111
10000
10001
10010
10011
10100
10101
10110
10111
11000
11001
11010
11011
11100
11101
11110
11111

Hence 32 combinations.
Blimey - I think I'm a geek!

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What is the formula for figuring how many possible combinations are available?

I have a model home with 5 options. You can chose and combination you want (from no options to all 5). How do I determine how many possible combinations I can have?

Thanks! :)



Ok. Here's the deal. When you are talking taking some number of objects from a group without regard to order, that is called a combination.

What you have a group of five options, but you can choose any number of them or none at all.

Lets's say you choose none of the options, there is only 1 way to do that.

If you take only one option, there are 5 choices.

If you take two options, there are 10 ways to do that.

and so on.

It all adds up to 1 + 5 + 10 + 10 + 5 + 1 = 32

Walt



5 options --> 2^5 = 32

For Great Deals on Gear


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I've always liked the idea of factorials but I too thought it was used to find a number of possibilities, ie, if I had five individual number and I would take the factorial of 5 to find the number of possible combinations. is this right?
Somebody please enlighten me on one.
Inveniam Viam aut Faciam
I'm back biatches!

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Abnother question:
If I had a lock with for distinct rows and 10 numbers each, how many combination possibilities are there?



10 choices for each combination -

10x10x10x10 (the lock counts from 0000 up to 9999)

if it was letters, it would be 26x26x26x26
if it was 2 letters and 2 numbers, then 26x10x26x10

and so on - that should answer any similar question going forward

...
Driving is a one dimensional activity - a monkey can do it - being proud of your driving abilities is like being proud of being able to put on pants

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I've always liked the idea of factorials but I too thought it was used to find a number of possibilities, ie, if I had five individual number and I would take the factorial of 5 to find the number of possible combinations. is this right?
Somebody please enlighten me on one.



In this case, each option has two possibilities, and choosing one option does not preclude other options being chosen, if I understood the original problem correctly.

So each option has two possibilities, with a total of five options, which works out to 2^5=32.

If each option had three possibilities, the total number of possibilities would be 3^5. With four possibilities, the answer would be 4^5.

Now for the quiz :P:

How high can one count on their hands, assuming both hands are used, and they each have five fingers?

For Great Deals on Gear


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5 options --> 2^5 = 32



32 is correct if you assume each of the options is independent, and each option can have only two values.

Some options may have more than two values. Paint color, for example. Or paint finish: matte, eggshell, semi-gloss, gloss, satin.

Some options may be dependent on others. For example, one style of cabinet door may be available only in white laminate, while another may be available in oak, maple, or cherry.

There's not enough given information for a complete answer.

Mark

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