Math Is Fun Forum

ddzc

Member

Registered: 2011-12-21

Posts: 2

Calculating Possibilities and Combinations

Hi everyone,

I have a situation which I need help calculating.

I have 15 selections to choose from and each selection has a 50/50 ratio of being correct. I want to figure out how many combinations I can choose for each selection in order to cover all possibilities. On each of the 15 selections, one number must be chosen. For example, for the first selection, I must select 1 or 2. For the second I must select 3 or 4, etc.

Example:

1 - 2
3 - 4
5 - 6
7 - 8
9 - 10
11 - 12
13 - 14
15 - 16
17 - 18
19 - 20
21 - 22
23 - 24
25 - 26
27 - 28
29 - 30

So one total combination is: 1-3-5-7-9-11-13-15-17-19-21-23-25-27-29. Another combination would be: 2-4-6-8-10-12-14-16-18-20-22-24-26-28-30. Another would be 1-4-6-8-10-11-14-16-17-20-21-24-26-27-30. The list goes on...so that's 3 different possibilities I just listed. Now, what I'm looking for is the total number of all combination to cover all possibilities when selecting.

Anyone know how I can calculate this?

Thank You,
Dan

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Calculating Possibilities and Combinations

Hi ddzc;

Welcome to the forum!

You have 2^15 = 32768 ways of selecting those numbers.

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In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

ddzc

Member

Registered: 2011-12-21

Posts: 2

Re: Calculating Possibilities and Combinations

Oh ok, didn't realize it was that simple...thanks a lot

anonimnystefy

Real Member

From: Harlan's World

Registered: 2011-05-23

Posts: 16,049

Re: Calculating Possibilities and Combinations

hi ddzs

didn't you get an answer on the other forum?

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