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	Pick
A) 6%	B) 5%	C) 12%	D) 10%	E) 8%
S.I. for 3 years = Rs. (12005 - 9800) = Rs. 2205.   S.I. for 5 years = Rs.	2205/3x 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