An irrational number in-between 7.7 and 7.9

Someone me! if you’re smart you can solve this!

For the sequence [tex]a_{n} = 2n/(n+1)[/tex], what is the value of [tex]a_{10}[/tex]

The center on a target has a diameter of 5 inches. the whole target has a diameter of 25 inches. complete the explanation for what part of the whole target is the center. the center of the target takes up % of the whole target.