3. The difference between simple and compound interests compounded annually on a certain sum of money for 2 years at 12% per annum is Rs 72. What is the value of given sum (in Rs)?
8. A bank offers 15% compound interest per half year. A customer deposits Rs 8800 each on 1st January and 1st July of a year. At the end of the year, the amount he would have gained by way of interest is _____.
9. If the amount received at the end of 2nd and 3rd year at Compound Interest on a certain Principal is Rs 1,800, and Rs 1,926 respectively, what is the rate of interest?