A sum of Rs.5000 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.	Pick.
A) 2888
B) 3120
C) 2877
D) 2999
E) 3250
Let A be the amount received at the end of the three years.   A = 5000[1 + 10/100][1 + 20/100][1 + 25/100]   A = (5000 * 11 * 6 * 5)/(10 * 5 * 4)   A = Rs.8250   So the interest = 8250 - 5000 = Rs.3250   Answer: 3250
<result>E</result>
A sum of Rs.5000 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.