#### Answer

$\left(-\infty,14 \right)$

#### Work Step by Step

$\bf{\text{Solution Outline:}}$
Use the properties of inequality to solve the given inequality, $
3\lt5-\dfrac{t}{7}
.$
$\bf{\text{Solution Details:}}$
Using the properties of inequality, the given is equivalent to
\begin{array}{l}\require{cancel}
3\lt5-\dfrac{t}{7}
\\\\
7(3)\lt7\left( 5-\dfrac{t}{7} \right)
\\\\
21\lt35-t
\\\\
t\lt35-21
\\\\
t\lt14
.\end{array}
Hence, the solution set is $
\left(-\infty,14 \right)
.$