The interest earned on 7600 from Jan to July will be 7600×20×
1
100
(Since rate of interest is 5 % per 6 months) = 76×20=1520 Hence, 7600 will amount to 9120. He adds another 7600 to this. So the net amount becomes 9120+7600=16,720. Now interest earned on this amount in a period of 6 months will be 16720×20×
1
100
=3344 So the final amount will be 16720+3344=20064 Total money he deposited = 7600+7600=15200 Hence, amount earned via interest = 20064−15200=Rs.4864