Question : On a certain sum, the difference between compound interest and simple interest at 10% per annum for 2 years is Rs.250. The sum is _________.

Question : Ramesh borrowed INR 15,000 at a certain rate of simple interest from a bank. He repaid (the principal but not interest) INR 6,000 after 5 years, and after 5 more years he paid  INR 18,600 and settled his account. Find the rate of simple interest per annum.

Question : Rekha invested a sum of Rs. 12000 at 5% per annum compound interest. She received an amount of Rs. 13230 after $n$ years. Find $n$.

Question : Ramesh borrowed some money at a rate of 5% per annum for the first four years, 8% per annum for the next six years, and 12% per annum for the period beyond ten years. If the total interest paid by him at the end of twelve years is INR 9,016, then find the money borrowed by

Question : A sum amount doubles in 8 years by simple interest. Then the rate of simple interest per annum is: