$$ -2 + \dfrac{2}{5} + \dfrac{-2}{15} $$
It can be written as
$$ \dfrac{-2}{1}+ \dfrac{2}{5} + \dfrac{-2}{15} $$
LCM of $$1 , 5 $$ and $$15$$ is $$15$$
$$ = \dfrac{-2 \times 15}{1 \times 15} + \dfrac{2 \times 3}{5 \times 3} + \dfrac{-2 \times 1}{15 \times 1} $$
By further calculation
$$ = \dfrac{-30}{15} + \dfrac{6}{15} + \dfrac{-2}{15} $$
So we get
$$ = \dfrac{-30 + 6 - 2}{15} $$
$$ = \dfrac{-32 + 6}{15} $$
$$ = \dfrac{-26}{15} $$