A sum of money at simple interest amounts to Rs 800 in 2 years and to Rs 1200 in 6 years. The sum is……………

A sum of money at simple interest amounts to Rs 815 in 3 years and to Rs 854 in 4 years. The sum is (a) Rs 650 (b) Rs 690 (c) Rs 698 (d) Rs 700

A sum of money at simple interest amounts to Rs.1,012 in 2 1/2 years and to Rs. 1,067.20 in 4 years. The rate of interest per annum is :

If a certain sum of money at simple interest amounts to Rs. 5184 in 2 years and to Rs. 5832 in 3 years, what is the sum and the rate of interest?