I am in needeth of a p'rson yond can holp me solveth thy problem(Pref'rably CPhill)

1.16 x = 55680      solve for 'x'

If your salary was increase 16% to equal $55,680, we can set up the equation where x is your salary before the increase 1.16x= $55680, solving for x we get $48,000. 

Here is thy answereth. xD

Hope it helps!