Chapter 3 - Equations and Problem Solving - 3.1 - Solving First-Degree Equations - Problem Set 3.1 - Page 100: 49

$n=\dfrac{3}{10}$

Multiplying both sides of the equation by $ \dfrac{3}{2} $ (which is the reciprocal of 2/3) and using the properties of equality, the value of the variable that satisfies the given equation, $ \dfrac{2}{3}n=\dfrac{1}{5} ,$ is \begin{array}{l}\require{cancel} n=\dfrac{1}{5}\cdot\dfrac{3}{2} \\\\ n=\dfrac{3}{10} .\end{array}