+7188 $${\mathtt{8}}{\mathtt{\,-\,}}{\frac{\left({\frac{{\mathtt{3}}}{{\mathtt{4}}}}\right)}{{\mathtt{2}}}}{\mathtt{\,-\,}}\left({\frac{{\mathtt{1}}}{{\mathtt{2}}}}\right) = {\frac{{\mathtt{57}}}{{\mathtt{8}}}} = {\mathtt{7.125}}$$
It doesn't equal 2 1/2
It equals 7 1/8
