The given number is
[tex]5^{-1}[/tex]Here we need to use a power property
[tex]a^{-n}=\frac{1}{a^n}[/tex]As you can see, the property allows us to move the position of the power in order to have a positive exponent. Let's do that
[tex]5^{-1}=\frac{1}{5}[/tex]