#### Answer

$n\lt2$

#### Work Step by Step

Multiplying both sides by the $LCD=
20
$ and then using the properties of inequalities, the solution to the given inequality, $
\dfrac{2n}{5}-\dfrac{n}{4}\lt\dfrac{3}{10}
,$ is
\begin{array}{l}\require{cancel}
4(2n)-5(n)\lt2(3)
\\\\
8n-5n\lt6
\\\\
3n\lt6
\\\\
n\lt\dfrac{6}{3}
\\\\
n\lt2
.\end{array}