Question

How do you calculate combinations of 10 numbers?

Answer 1

If `r` numbers are chosen, then the number of all combinations can be found by

`C(10,r)={P(10,r)}/{r!}={10 cdot 9 cdot cdots cdot (10-r+1)}/{r!}`

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Example

If `r=3`, then

`C(10,3)={10 cdot 9 cdot 8}/{3 cdot 2 cdot 1}=120` combinations

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I hope that this was helpful.