[tex]2\dfrac{1}{5}+1\dfrac{1}{10}=2+\dfrac{1}{5}+1+\dfrac{1}{10}=(2+1)+\left(\dfrac{1}{5}+\dfrac{1}{10}\right)\\\\=3+\left(\dfrac{1\cdot2}{5\cdot2}+\dfrac{1}{10}\right)=3+\left(\dfrac{2}{10}+\dfrac{1}{10}\right)=3+\dfrac{2+1}{10}=\boxed{3\dfrac{3}{10}}[/tex]