Answer
$${\text{ }}P\left( {9,2} \right) = \frac{1}{{2520}}$$
Work Step by Step
$$\eqalign{
& P\left( {9,2} \right) \cr
& {\text{Use the permutation formula }}P\left( {n,r} \right) = \frac{{n!}}{{\left( {n - r} \right)!}} \cr
& {\text{ }}P\left( {9,2} \right) = \frac{{2!}}{{\left( {9 - 2} \right)!}} \cr
& {\text{Evaluate and simplify}} \cr
& {\text{ }}P\left( {9,2} \right) = \frac{{2!}}{{7!}} \cr
& {\text{ }}P\left( {9,2} \right) = \frac{2}{{5040}} \cr
& {\text{ }}P\left( {9,2} \right) = \frac{1}{{2520}} \cr} $$
