Chapter 5 - Number Theory and the Real Number System - Chapter Summary, Review, and Test - Review Exercises - Page 335: 55

$\dfrac{11}{15}$

Perform multiplication first: \begin{align*} &=\frac{1}{3}+\frac{4}{10} \end{align*} Make the fractions similar using their LCD of $30$, then add to obtain: \begin{align*} &=\frac{1\cdot10}{3\cdot10} + \frac{4\cdot3}{10\cdot3}\\\\ &=\frac{10}{30} + \frac{12}{30}\\\\ &=\frac{22}{30}\\\\ &=\frac{11}{15} \end{align*}