A sum of Rs. 12,500 amounts to Rs. 15,500 in 4 years at the rate of simple interest. What is the rate of interest?  Pick.
A) 3%
B) 4%
C) 5%
D) 6%
E) 7%
S.I. = Rs. (15500 - 12500) = Rs. 3000.   Rate =(100 x 3000)/(12500 x 4)%	= 6%   answer :6%
<result>D</result>
A sum of Rs. 12,500 amounts to Rs. 15,500 in 4 years at the rate of simple interest. What is the rate of interest?