Question:
Find two rational numbers between $\frac{1}{5}$ and $\frac{1}{2}$.
Solution:
$R$ ational number between $\frac{1}{5}$ and $\frac{1}{2}=\frac{\left(\frac{1}{5}+\frac{1}{2}\right)}{2}=\frac{\frac{2+5}{10}}{2}=\frac{7}{20}$
$R$ ational number between $\frac{1}{5}$ and $\frac{7}{20}=\frac{\left(\frac{1}{5}+\frac{7}{20}\right)}{2}=\frac{\frac{4+7}{20}}{2}=\frac{11}{40}$
Therefore, two rational numbers between $\frac{1}{5}$ and $\frac{1}{2}$ are $\frac{7}{20}$ and $\frac{11}{40}$.