The operation $\otimes$ is defined by $a \otimes b=\frac{a}{b}+\frac{b}{a}$. What is the value of $4 \otimes 8$ ?
(A) $\frac{1}{2}$
(B) 1
(C) $\frac{5}{4}$
(D) 2
(E) $\frac{5}{2}$
From the given definition,

$$
4 \otimes 8=\frac{4}{8}+\frac{8}{4}=\frac{1}{2}+2=2 \frac{1}{2}=\frac{5}{2}
$$

ANswer: (E)