Question : A person invested a sum of INR 10,500 at $x$% per annum at simple interest and a sum of INR 13,500 at $(x + 2)$% p.a. at simple interest. If the total interest earned on both investments for 3 years is INR 7,650, then the rate of interest on the first investment is:

Question : Sudeep invested $\frac{1}{8}$th of a certain sum at 5% p.a. for two years and $\frac{3}{5}$th of the sum at 6% p.a. for two years and the remaining at 10% p.a. for two years. If the total interest received is INR 1,674, then the total sum invested is:

Question : The compound interest on a certain sum invested for 2 years at 10% per annum is INR 1,522.50, the interest being compounded yearly. The sum is:

Question : A certain sum (in INR) is invested at simple interest at y% per annum for $3 \frac{1}{2}$ years. Had it been invested at (y + 4)% per annum at simple interest, it would have fetched INR 4,452 more as interest. What is the sum?

Question : Peter invested a certain sum of money in a scheme paying 10% simple interest per annum, while Rachel invested half of the sum that Peter invested in a scheme paying 10% interest per annum compounded annually. Also, while Peter invested for 2 years, Rachel invested for 3 years.