Mathematics

Say the man has income $x$ . He lost $20\%= \dfrac{1}{5}$ of his income. The remainder is then $\dfrac{4}{5}x$

Now he spends $25\% = \dfrac{1}{4}$ of the remainder. He now has $\dfrac{3}{4}$ of the remainder left, which is equivalent to $\dfrac{3}{4} \left(\dfrac{4}{5}x \right) = \dfrac{3}{5}x$

This remaining amount is equal to $480$ Rupees. Therefore:

$\dfrac{3}{5}x = 480\\ x=480 \times \dfrac{5}{3} = 800$

The man has an income of $\boxed{800}$ Rupees

man looses= 20% or ({1/5})

man uses= (1-({1/5})of 25% or ({1/4})

according to question= = (1-{1/5}) of (1-{1/4})=480

                                        = ({4/5})x({3/4})=480

                                        = ({3/5})= 480

                                         =  480x({5/3})    

                                          =  800

hence, rupees 800 were with him at first.

His income is(I write it in a short way): $480/[(1-\frac{1}{4}) \times(1-\frac{1}{5})]=800$ Hence, the answer is $\boxed{Rs.800}$

Let Us Try A Easy And Shortcut Method To Solve This Problem.
Let Us Consider The Basic Income As 100
Now, As The Man Looses 20% Income,
100 - $\frac{20}{100}$ x 100 = 80

Now, As he Spends 25% Of his Remainder Income,
80 - $\frac{25}{100}$ x 80 = 60

Now, if
100 Gives 60
Then, x Gives 480 ....(Where 'x' is Actual Income and 480 Is Left Income)

x = $\frac{480 * 100}{60}$
x = $\boxed{800}$