aa+ba+cc+dc+ff+ef=3k+1
$ 1 + \frac{b}{a} +1+ \frac{d}{c} +1+ \frac{e}{f}= \frac{3}{k+1} $
$ \frac{b}{a} + \frac{d}{c} + \frac{e}{f} = \frac{3}{k+1}-1 $
$ \frac{b}{a} + \frac{d}{c} + \frac{e}{f} = \frac{b+d+e}{a+c+f} = \frac{3}{k+1}-1 $
$ \frac{a+c+f}{b+d+e}= \frac{k+1}{3-k-1} $