A sum of money amounts to Rs. 9800 after 5 years and Rs. 12005 after 8 years at the same rate of simple interest. The rate of interest per annum is: Choose the correct choice from the following:
A) 5% B) 8% C) 12% D) 15% E) 10%
S.I. for 3 years = Rs. (12005 - 9800) = Rs. 2205.   S.I. for 5 years = Rs.	((2205/3)x 5)	= Rs. 3675   Principal = Rs. (9800 - 3675) = Rs. 6125.   Hence, rate =((100 x 3675)/(6125 x 5))%	= 12%   Answer :12%
<result>C</result>
A sum of money amounts to Rs. 9800 after 5 years and Rs. 12005 after 8 years at the same rate of simple interest. The rate of interest per annum is: