For the quarterly interest,
Time = (6/12) year x 4 = 2 quarterly
Rate = 20/4 = 5%
(∴ On quarterly interest time is multiplied by 4 and rate is divided by 4)
Hence,required amount = Principal (1 + Rate/100)Time
= 2000(1 +5/10)2
= 2000(21/20)2
= Rs. 2205