A sum of money amounted to Rs.720 in 2 years and Rs.792 in 3 years when interest is compounded annually. The annual rate of interest , (in%) is:

A person can buy a refrigerator for Rs.15,850 on cash payment or in installments for every year at 10% p.a for four years compounded annually. What is the approximate annual installment that he should pay?

A sum of Rs. 2000 amounts to Rs. 4000 in two years at compound interest. In how many years does the same amount becomes Rs. 8000. 

Raman took a loan of Rs. 15000 from Laxman. He was agreed that for the first three years rate of interest charged would be at 8% Simple Interest per annum and at 10% Compound Interest (compounded, annually) from the fourth year onwards. Ram did not pay anything until the end of the fifth year. How much would he repay if he clears the entire amount, only at the end of fifth year? (inRs.)

A sum amounts to ₹ 6480 in 4 years and ₹ 9600 in 8 years when it is compounded annually. Find the sum?

A bank pays half-yearly compound interest at the rate of 5% p.a. . A person deposited Rs 1600 on January 1 and a similar amount on July 1 . Explain how much interest will be paid by the bank at the end of the year.