A bank lends money at 12% per annum on simple interest. A customer borrows ₹ 50,000 for 9 months and repays after receiving a 5% rebate on total interest amount. What effective annual interest rate did he pay?

A sum of ₹ 80,000 is invested at 6% p.a. at simple interest for the first year, then 8% p.a. for the next 2 years (still simple interest). What is the total interest earned over the 3 year period?

A certain sum on $13\frac{1}{2}\%$ per annum simple interest amounts to Rs. 2502.50 in 4 years. Find the sum.

What sum of money will amount to Rs. 520 in 5 years and to Rs 568 in 7 years on simple interest?

The difference between the amounts of compound interest and simple interest on the same amount invested at the same rate for 2 years in Rs. 32. If the interest rate is 4% per annum, calculate the amount invested.(in Rs.)

Mr. X invested one fourth of his capital at 8%, one third at 7% and the remaining part at 10%. If his annual simple interest on this investment is Rs 510, then the total capital invested by Mr. X is?

A sum of Rs 10,000 becomes Rs 14,400 on compound interest in 2 years. What is the rate of interest per annum ?