what is three fourths minus two sevenths
$${\frac{{\mathtt{3}}}{{\mathtt{4}}}}{\mathtt{\,-\,}}\left({\frac{{\mathtt{2}}}{{\mathtt{7}}}}\right) = {\frac{{\mathtt{13}}}{{\mathtt{28}}}} = {\mathtt{0.464\: \!285\: \!714\: \!285\: \!714\: \!3}}$$