cuanto es un cuarto menos tres medios?

$${\frac{{\mathtt{1}}}{{\mathtt{4}}}}{\mathtt{\,-\,}}{\frac{{\mathtt{3}}}{{\mathtt{2}}}} = {\frac{{\mathtt{1}}}{{\mathtt{4}}}}{\mathtt{\,-\,}}{\frac{{\mathtt{6}}}{{\mathtt{4}}}} = {\mathtt{\,-\,}}{\frac{{\mathtt{5}}}{{\mathtt{4}}}}$$