# Thread: How many possible conbination can be if a have 128 elements?

1. ## How many possible conbination can be if a have 128 elements?

If i have 2 elements a total conbination can be 2*2 = 4 right?

Matrix 2 * 2

* *
* *

matrix 3*3

* * *
* * *
* * *

so if have 128 elements, 128 * 128 is the toltal possible elements that can be?

I am right?

2. Are you saying that you have 128 distinguishable elements, and you're trying to find the number of combinations of any two of them, assuming repetition is allowed?

Thank you!

3. A element can be a zero or one ( on or off ) like a bit.

so how many possible conbination can happens if a have 128 elements

4. 2^128 will be the right answer?

5. Hello darkmoon123
Originally Posted by darkmoon123
A element can be a zero or one ( on or off ) like a bit.

so how many possible conbination can happens if a have 128 elements
2^128 will be the right answer?
Yes, it will. The number of ways of choosing each bit is $2$; there are $128$ choices to be made, so there are $2^{128}$ combinations altogether.

What I'm not too clear about is what this has to do with your matrix pattern:
If i have 2 elements a total conbination can be 2*2 = 4 right?

Matrix 2 * 2

* *
* *

matrix 3*3

* * *
* * *
* * *

so if have 128 elements, 128 * 128 is the toltal possible elements that can be?

I am right?
This, your first posting, appears to fit in with what stapel said, which is:
Are you saying that you have 128 distinguishable elements, and you're trying to find the number of combinations of any two of them, assuming repetition is allowed?
In which case the answer is $128^2$.

So let's be clear:

• If you have $128$ items, each of which can be chosen in $2$ ways, then there are $2^{128}$ ways to choose all $128$ items.

• If you have $2$ items, each of which can be chosen in $128$ ways, then there are $128^2$ ways to choose the $2$ items.