1. At an annual simple interest rate of 10%, how much money will become 14,000 rupees in 4 years?

(a) ₹ 12500 (b) ₹ 12000 (c) ₹ 12600 (d) ₹ 10000

2. A farmer deposited some money in the village post office. After 4 years, he found that the total amount including interest had become ₹434. He calculated that the interest he received was \(\frac{6}{25}\) of his principal amount. Find how much money he had originally deposited and what annual rate of simple interest the post office gave.

3. At an annual interest rate of 4%, how much money should be invested so that the total amount becomes ₹3600 in 5 years?

4. At an annual simple interest rate of 5%, a person deposits some money in the bank. After 5 years, how much total amount will he receive, if the principal is 12,500 rupees less than the total amount (principal + interest?

5. If the total amount becomes 966 rupees at an annual simple interest rate of 3% in 5 years, the principal amount will be -

(a) 480 rupees (b) 408 rupees (c) 404 rupees (d) 840 rupees

6. At an annual simple interest rate of 5%, how many years will it take for the interest on ₹6000 to become ₹1500?

(a) 3 years (b) 30 years (c) 5 years (d) 15 years

7. What will be the total amount of 450 rupees after 3 years at an annual simple interest rate of 4%?

(a) ₹ 135 (b) ₹ 180 (c) ₹ 504 (d) ₹ 600

8. At an annual simple interest rate of 6%, in how many years will the interest on ₹\(x\) amount become ₹\(\frac{9x}{25}\)? Find the value of the time.

(a) 6 years (b) 8 years (c) 10 years (d) 12 years

9. What should be the annual rate of simple interest (in percent) so that the interest on a sum of money for 10 years becomes \(\frac{2}{5}\) of the total amount (principal + interest)?

10. What should be the annual simple interest rate (in percentage) so that the interest on a sum of money for 6 years becomes \(\frac{18}{25}\) of the principal?

11. What principal amount will become ₹930 in 6 years at an annual simple interest rate of 4%?

(a) ₹ 890 (b) ₹ 750 (c) ₹ 690 (d) ₹ 520

12. A bank provides an annual simple interest rate of 5%. At the beginning of the year, Mr. Dip deposited 15,000 rupees. Three months later, he withdrew 3,000 rupees, and three months after withdrawing the amount, he deposited 4,000 rupees again. At the end of the year, how much money will Mr. Dip receive from the bank, including interest?

13. Two friends borrowed ₹15,000 from a bank at an annual simple interest rate of 12% to run a small business together. Calculate how much interest they will have to pay after 4 years.

14. At an annual simple interest rate of 5.25%, Shova Devi deposited a certain amount of money in a bank. After 2 years, she received ₹840 as interest. Calculate how much money she had deposited.

15. Mr. Rathin deposits money in the bank for each of his two daughters in such a way that when each daughter turns 18 years old, she will receive ₹120000. The bank offers simple interest at an annual rate of 10%. The current ages of the daughters are 13 years and 8 years respectively. Calculate how much Mr. Rathin deposited in the bank for each daughter.

16. At an annual interest rate of 4%, for how much money will the difference between the simple interest and the compound interest for 2 years be 80 rupees? Let’s calculate and write it down.

17. At an annual simple interest rate of 8%, in how many years will 5000 rupees grow to 7400 rupees?

(a) 3 years (b) 4 years (c) 5 years (d) 6 years

18. At an annual simple interest rate of 8%, how much interest will make the principal amount grow to \(\cfrac{7}{5}\) times its original value?

(a) 4 years (b) 5 years (c) 6 years (d) 7 years

19. At what annual interest rate will the interest on a principal amount become \(\cfrac{5}{16}\) of the principal in 6\(\cfrac{1}{4}\) years?

(a) 3% (b) 4% (c) 5% (d) 6%

20. What annual rate of simple interest will make the interest on a sum over 10 years equal to \(\cfrac{2}{5}\) of the total amount?

(a) \(6\frac{1}{3}\%\) (b) \(6\%\) (c) \(6\frac{2}{3}\%\) (d) \(2\frac{1}{6}\%\)

21. If the simple interest on ₹850 for 3 years and on ₹1250 for 4 years at the same rate amounts to ₹302 in total, then what will be the annual rate of interest?

(a) 3% (b) 5% (c) 7% (d) None of the above

22. If a certain principal amount triples in 15 years at simple interest, then the annual rate of simple interest will be —

(a) \(13\frac{1}{3}\%\) (b) \(12\frac{1}{3}\%\) (c) \(11\frac{1}{3}\%\) (d) \(10\frac{1}{3}\%\)

23. If a sum of money becomes 4 times its original amount in *n* years at a fixed annual compound interest rate, then in how many years will it become 4 times?

24. If a certain amount of money doubles in 4 years at a fixed annual compound interest rate, in how many years will it become four times?

25. What should be the annual rate of simple interest (in percentage) so that the interest earned in 4 years becomes \( \frac{2}{5} \) of the principal amount?

26. What should be the annual rate of simple interest (in percentage) so that the interest earned in 4 years becomes \(\frac{8}{25}\) of the principal amount?

27. If a sum of money doubles in \(n\) years at a fixed annual compound interest rate, then in how many years will it become 4 times?

28. Rekha received ₹100,000 upon retirement. She deposited part of the amount in a bank and the rest in a post office, earning ₹5,400 as annual interest. The annual simple interest rates at the bank and post office are 5% and 6% respectively. How much money did she deposit in each place?

29. If the simple interest for \(n\) years at an annual rate of \(r\%\) is \(\frac{pnr}{25}\) rupees, then the principal amount will be _____ rupees.

30. Calculate the amount of money for which the monthly interest will be 1 rupee at an annual simple interest rate of 5%.