Let $f : [0, \infty) \to [0, \infty)$ be an D4367: Unsigned real function such that

(i)	$f$ is a D1760: Riemann integrable real function on $[0, b]$ for every $b \in [0, \infty)$
(ii)	\begin{equation} \lim_{t \to \infty} f(t) = 0 \end{equation}

Then \begin{equation} \lim_{x \to \infty} \frac{1}{x} \int^x_0 f(t) \, d t = 0 \end{equation}