$ \dfrac{\dfrac{2}{7} + \dfrac{2}{5} + \dfrac{2}{17} - \dfrac{2}{293}}{\dfrac{3}{7} + \dfrac{3}{5} + \dfrac{3}{17} - \dfrac{23}{293}}$
$\\$
$ = \dfrac{2( \dfrac{1}{7} + \dfrac{1}{5} + \dfrac{1}{17} - \dfrac{1}{293})}{3(\dfrac{1}{7} + \dfrac{1}{5} + \dfrac{1}{17} - \dfrac{1}{293})} = \dfrac{2}{3}$