Converting annual interest rates to quarterly we get 20/4 = 5 percent. Now there are three compounds (9 months has 3 sets of 3 months) so the final amount can be Calculated as follows

16000*(1.05)^3 = 18522 18522 - 16000 = Compound interest = 2522.

If difference between the compounded interest and the simple interest on a certain sum at 10% per annum for 2 years is Rs.52, then what would be the the sum?