A sum of Rs. 2500 amounts to Rs. 3875 in 4 years at the rate of simple interest. What is the rate of interest? Choose the correct choice from the following answers:
A) 12.25%
B) 12%
C) 6%
D) 13.75%
E) 13.95%
Explanation :   Simple Interest, SI = (3875 - 2500) = Rs.1375   Principal, P = Rs. 2500   Time, T = 4 years   R = ?   R=100×SI/PT   =100×1375/2500×4   100×1375/10000   =13.75%
<result>D</result>
A sum of Rs. 2500 amounts to Rs. 3875 in 4 years at the rate of simple interest. What is the rate of interest?