When the numbers $3, \frac{5}{2}$ and $\sqrt{10}$ are listed in order from smallest to largest, the list is
(A) $3, \frac{5}{2}, \sqrt{10}$
(B) $\frac{5}{2}, 3, \sqrt{10}$
(C) $\sqrt{10}, \frac{5}{2}, 3$
(D) $\frac{5}{2}, \sqrt{10}, 3$
(E) $3, \sqrt{10}, \frac{5}{2}$
Since $3=\frac{6}{2}$ and $\frac{5}{2}<\frac{6}{2}$, then $\frac{5}{2}<3$.

Since $3=\sqrt{9}$ and $\sqrt{9}<\sqrt{10}$, then $3<\sqrt{10}$.

Thus, $\frac{5}{2}<3<\sqrt{10}$, and so the list of the three numbers in order from smallest to largest is $\frac{5}{2}, 3, \sqrt{10}$.

ANswer: (B)