When the numbers $\sqrt{5}, 2.1, \frac{7}{3}, 2.0 \overline{5}, 2 \frac{1}{5}$ are arranged in order from smallest to largest, the middle number is
(A) $\sqrt{5}$
(B) 2.1
(C) $\frac{7}{3}$
(D) $2.0 \overline{5}$
(E) $2 \frac{1}{5}$
We write each of the five numbers as a decimal in order to be able to arrange them in order from smallest to largest:

$$
\begin{aligned}
\sqrt{5} & =2.236 \ldots \\
 2.1 & =2.1 \\
\frac{7}{3} & =2.333 \ldots \\
 2.0 \overline{5} & =2.055 \ldots \\
 2 \frac{1}{5} & =2.2
\end{aligned}
$$

So in order from smallest to largest, we have $2.0 \overline{5}, 2.1,2 \frac{1}{5}, \sqrt{5}, \frac{7}{3}$. The number in the middle is $2 \frac{1}{5}$. ANswer: (E)