The compound interest earned by Sunil on a certain amount at the end of two years at the rate of 8% p.a. was Rs.2828.80. Find the total amount that Sunil got back at the end of two years in the form of principal plus interest earned.

A. Rs.18,828.80
B. Rs.19,828.80
C. Rs.18,028.80
D. Rs.17,828.80
E. None of these
Explanation:
Let the sum be Rs.P
P{ [ 1 + 8/100]2 – 1 } = 2828.80
P(8/100)(2 + 8/100) = 2828.80 [a2 – b2 = (a – b) ( a + b)] P = 2828.80 / (0.08)(2.08) = 1360/0.08 = 17000 Principal + Interest = Rs. 19828.80