Suppose the rate of interest is r% per annum
Then
22000(1 + r/100)2 = 22000 + 5596.8
=> (1 + r / 100)2 = 27596.8/ 22000
= 275968/ 220000 = 12544 / 10000
= (112/100)2 = (1 +12/100)2
=> r = 12% - See more at: http://education.abn-andhrajyothy.com/arithmetic-ability16-10-2014#sthash.i5VYhSo0.dpuf
Suppose the rate of interest is r% per annum
Then 22000(1 + r/100)2 = 22000 + 5596.8
=> (1 + r / 100)2 = 27596.8/ 22000
= 275968/ 220000 = 12544 / 10000
(112/100)2= (1 +12/100)2
=> r = 12 %
Now , R = 12 %
Hence option 3.
