binomial(5+5,5) is binomial(10,5) and Can also be written as:
10C5
(n,r)C(10,5)......I think that is how u can write it.
it means:
(n!)/(((n-r)!)r!)
so in this case it is:
10!/((10-5)!*5!)
10!/(5!*5!)
(10*9*8*7*6)/(5*4*3*2)
(9*2*7*2) = 252
In words it means you have n things and how many ways can u choose r things out of the n.
FYI n and r are variables.
Here is more in better detail AND LaTeX than me
More detail
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