The compound interest earned on a sum for the second and the third years are $1200 and $1260 respectively. What is the rate of interest?
Choose the correct option:
A) 5%
B) 8%
C) 11%
D) 14%
E) 18%
1260 - 1200= 
<gadget id="calculator">1260 - 1200</gadget>
<output>60</output>
60 is the rate of interest on $1200 for one year.   The rate of interest= (100 * 60) / (1200)= 
<gadget id="calculator">(100 * 60) / (1200)</gadget>
<output>5</output>
5%   The answer is 5%.
<result>A</result>
The compound interest earned on a sum for the second and the third years are $1200 and $1260 respectively. What is the rate of interest?