Question

A man’s net income, after paying income tax at 20% is 55,640. Find his gross income.

Answer 1

 Let Net Income = x

(100-20)% of x = 55640

80% of x = 55640

x = 55640*100/80 = 69550

Answer 2

let the gross income be x,
then, x-(x/5)=55640
4x=5*55640
x=5*55640/4