CAT 2017 [slot 1] Question with solution 33

$f(3) = \frac{15 + 2}{9 - 5} = \frac{17}{4}$
$f(f(3)) = \frac{5×17/4 + 2}{3×17/4 - 5} = \frac{93/4}{31/4} = \frac{93}{31} = 3$
$g(f(f(3))) = 3^2 - 3×2 - 1 = 2$