$\displaystyle \sum_{n=1}^{\infty} \frac{3n + 2}{n} ({8/5})^n$

The question asks me to compute the value of p for the series with the root test. I took the root test and got:

$\displaystyle \sum_{n=1}^{\infty} \frac{3n +2}{n} ({8/5})$ , as with the limit of n going to infinity. By that notion, I got 3 x (8/5), which is 24/5, but the answer is incorrect. Can anyone tell what I am doing wrong?

Thanks