A person gave 20% of his income to his elder son, 30% of remaining to the younger son and 10% of the balance, he donate to a trust. He is left with Rs. 10080. His income was :

Let Person income is 100x
20% his income give to elder son, i.e. 20x
Remaining income 100x -20x = 80x
Now 30% of his remaining income given to his younger son
i.e. 30% of 80x = 24x
Remain saving is 80x - 24x = 56x
Now 10% of his remaining income he donated to a trust
i.e. 10% of 56x = 5.6x
Remain income = 56x - 5.6x = 50.4x
According to question
50.4x = 10080
x = $$\frac{{10080}}{{50.4}}$$ = 200
Person income = 100 x 200 = Rs. 20000