KöMaL 2022 C1717

Let $x_1$ and $x_2$ denote the two real roots of the equation $15x^2-21x+7=0$. Find the exact value of the expression $\frac{x_1}{x_2}+\frac{x_2}{x_1}+\frac{1}{x_1}+\frac{1}{x_2}$