An amount at compound interest sums to Rs.17640/- in 2 years and to Rs.22932/- in 3 years at the same rate of interest. Find the rate percentage? Select
A) 5%
B) 7%
C) 9%
D) 11%
E) 30%
Explanation:   The difference of two successive amounts must be the simple interest in 1 year on the lower amount of money.   S.I = 22932/- - 17640/- = Rs. 5292/-   Rate of interest = (5292/22932) × (100/1) =&gt; 30%   Answer: Option 30%
<result>E</result>
An amount at compound interest sums to Rs.17640/- in 2 years and to Rs.22932/- in 3 years at the same rate of interest. Find the rate percentage?