A sum at simple interest at 1312 % per annum amounts to Rs. 2502.50 after 4 years. Find the sum

 Let sum be Rs.x then, S.I. =Rs. [ x * (27/2) * 4 * (1/100) ] = Rs. 27x/50 

Amount =Rs [ x + (27x/50)] = Rs.77x/50 

=> 77X/50 = 2502.50  

=>X= (2502.50 * 50)/77 = 1625 

Hence Sum = Rs.1625