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Introduction to counting with permutations and combinations
", "licence": "Creative Commons Attribution-ShareAlike 4.0 International"}, "statement": "How many ways can you choose $r$ distinct objects from $n$ possible objects?
\nThe answer depends upon whether the order of selection is important.
\nThe NUMBAS syntax for $P(n,r)$ and $C(n,r)$ is perm(n,r)
and comb(n,r)
.
For part a, choosing $\\var{r}$ from $\\var{n}$ distinct objects when order matters can be done in $P(\\var{n},\\var{r}) = \\var{perm(n,r)}$ ways.
\nFor part b, choosing $\\var{r2}$ from $\\var{n}$ distinct objects when order does not matter can be done in $C(\\var{n},\\var{r2}) = \\var{comb(n,r2)}$ ways.
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