Using combinations with 7 zeros and 3 ones

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amcavoy
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How many sequences are there consisting of seven 0's and three 1's? Example: 0101010000
I was thinking that I could solve this with combinations. However, I am unsure of how to use it in this case. If I remember correctly, the combinations are given by:

[tex]\begin{pmatrix}n \\ r\end{pmatrix}=\frac{n!}{r!\,\left(n-r\right)!}[/tex]

Hmm. Any thoughts on this? Am I on the right track with the above?

Thanks.
 
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There are [itex]2^{10}[/itex] ways of selecting the digits and [itex]_{10}C_3[/itex] ways of having three 1's.
 
Tide said:
There are [itex]2^{10}[/itex] ways of selecting the digits and [itex]_{10}C_3[/itex] ways of having three 1's.
Alright. I was thinking that it didn't matter if they were the same number; I could still use the formula above. Thanks for the confirmation :smile:.