A sum of Rs.48000 is invested at a compound interest for three years, the rate of interest being 10% p.a., 20% p.a. and 25% p.a. for the 1st, 2nd and the 3rd years respectively. Find the interest received at the end of the three years.	Choose the correct choice from the following.
A) 28880 B) 31200 C) 28770 D) 29990 E) 12770
Let A be the amount received at the end of the three years.   A = 48000[1 + 10/100][1 + 20/100][1 + 25/100]   A = (48000 * 11 * 6 * 5)/(10 * 5 * 4)   A = Rs.79200   So the interest = 79200 - 48000 = Rs.31200   Answer: 31200
<result>B</result>
A sum of Rs.48000 is invested at a compound interest for three years, the rate of interest being 10% p.a., 20% p.a. and 25% p.a. for the 1st, 2nd and the 3rd years respectively. Find the interest received at the end of the three years.