-3/5 + 2/3

$${\mathtt{\,-\,}}{\frac{{\mathtt{3}}}{{\mathtt{5}}}}{\mathtt{\,\small\textbf+\,}}{\frac{{\mathtt{2}}}{{\mathtt{3}}}} = {\frac{{\mathtt{1}}}{{\mathtt{15}}}} = {\mathtt{0.066\: \!666\: \!666\: \!666\: \!666\: \!7}}$$