A sum of Rs.1600 gives a simple interest of Rs.252 in 2 years and 3 months. The rate of interest per annum is 

Nitin borrowed some money at the rate of 6% p.a. for the first three years, 9 % p. a. for the next five years and 13 % p.a. for the period beyond eight years. If the total interest paid by him at the end of eleven years is ₹8,160, the money borrowed by him ( in ₹ ) was -  

A sum of ₹ 400 amounts to ₹ 480 in 4 years. What will it amount to if the rate of interest is increased by 2 %? 

Out of ₹ 20, 000 Narendra gives some amount on loan at simple interest rate 8 % per annum and rest amount at simple interest rate 4 / 3 % per annum. At the end of year he earns ₹ 800. The amount given at 8 % rate will be –