let the no. of oranges purchased be x.
cost price of oranges=5x.
he buys equal no. of bananas.
so no. of bananas=x.
cost price of x bananas=2x.
Now, he makes a profit of 20% on oranges.
therefore, selling price of oranges=5x+20%of 5x
=6x
profit on oranges=6x-5x=x
he makes a profit of 15% on bananas
therefore, selling price of bananas=2x+15% of 2x
=23x upon 10
profit on bananas=23x /10-2x=3x /10
Total profit made =x+3x /10=13x /10
According to ques,,, 13x /10=Rs 390
therefore x=300----Answer