Simple Interest Questions

• Simple Interest – Scaling the rate with fixed time: A certain principal becomes 3 times at 4% simple interest per annum. In the same time, at what annual simple interest rate would it become 6 times?
• Simple Interest – Find maturity amount: Kriya deposits ₹ 65,800 at a simple interest rate of 14% per annum for 4 years. What total amount will she receive at the end of 4 years?
• Simple Interest – Same time, different multipliers: In a certain time, a principal becomes 4 times at 5% per annum simple interest. In the same duration, at what simple interest rate will the principal become 8 times?
• Simple Interest – Time to quadruple at a given rate: At a simple interest rate of 10% per annum, in how many years will a sum of money become four times its original value?
• Simple Interest – Compare interests to find rate: For the same time period, the simple interest on ₹ 1230 for 2 years is ₹ 10 more than the simple interest on ₹ 1130 for 2 years. What is the annual simple interest rate?
• Simple Interest – Comparing two scenarios to find the principal: For a certain principal S, the simple interest in 2 years at 8% per annum is ₹ 110 more than the simple interest in 1 year at 5% per annum (on the same S). Find S.
• Simple Interest – Find principal from change in rate: A sum was invested for 4 years. If the annual simple interest rate had been 2% higher, the total interest would have been ₹ 56 more. What is the principal?
• Simple Interest – Scaling rate for a larger multiple in the same time: A certain principal becomes 6 times the original at a simple interest rate of 5% per annum. In the same time period, at what simple interest rate (per annum) would the principal become 12 times?
• Simple Interest – Time for a larger multiple at the same rate: A sum becomes twofold (double) in 6 years at a certain simple interest rate. At the same annual rate, in how many years will the same sum become tenfold?
• Simple Interest – Rate-gap from interest difference: The difference between the simple interest earned on ₹ 1,000 in 2 years from two banks is ₹ 20. What is the difference between their annual rates of interest?
• Simple Interest – Combine two loans at one rate: Raju lends ₹ 400 to Ajay for 2 years and ₹ 100 to Manoj for 4 years. He receives a total of ₹ 60 as simple interest from both. What is the annual simple interest rate?
• Simple Interest – Weighted-rate portfolio on one principal: Two-thirds of a sum is lent at 3% per annum, one-sixth at 6% per annum, and the remaining one-sixth at 12% per annum, all at simple interest. If the annual income is ₹ 25, what is the total principal?
• Simple Interest – Equalize two borrowers’ amounts due: Suresh borrows ₹ 800 at 6% per annum (simple interest) and Naresh borrows ₹ 600 at 10% per annum (simple interest). After how many years will the amounts due (principal + interest) be equal?
• Simple Interest – Split a principal into two parts with equal interest earned: A sum of ₹ 1,521 is split into two parts. On one part, the interest at 10% per annum for 5 years is equal to the interest on the other part at 8% per annum for 10 years. What are the two parts?
• Simple Interest – Find the rate from combined interest of two loans: Rashim lends ₹ 600 to Geeta for 2 years and ₹ 150 to Seeta for 4 years. Altogether, she receives ₹ 80 as simple interest. What is the annual rate of simple interest?
• Simple Interest – Interest equals a small fraction of principal: The simple interest on a sum of money is 1/144 of the principal. The number of years is equal to the rate per cent per annum. What is the rate per cent per annum?
• Simple Interest – Fractional interest and time-rate equality: The simple interest on a sum of money is 1/16 of the principal. The number of years is equal to the rate per cent per annum. Find the rate per cent.
• Simple Interest — Recover principal from given interest and partial year: What principal will earn a simple interest of Rs 55 in 9 months at a rate of 3 2/3% per annum?
• Simple Interest — Principal tripled after 5 years: A sum earns Rs 200 simple interest in the first 5 years. In the next 5 years, the principal is tripled at the same rate. What is the total interest over 10 years?
• Simple Interest — Infer rate, then compute four times the rate: Ramesh invests 10% of Rs 10000 at simple interest. After 3 years, the amount is Rs 2500. Find 4 times the actual annual interest rate.