1. 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.

2. At an annual simple interest rate of \(r\%\), if the total interest on a principal for \(n\) years is \(\cfrac{pnr}{25}\) rupees, then the amount of the principal is –

(a) \(2p\) rupees (b) \(4p\) rupees (c) \(\cfrac{p}{2}\) rupees (d) \(\cfrac{p}{4}\) rupees

3. If the interest on a principal for 5 years is \(\cfrac{1}{4}\) of the principal, then the annual interest rate will be –

(a) 5% (b) 10% (c) 15% (d) 20%

4. If the annual simple interest on a principal is \(\cfrac{1}{9}\) of it, then what will be the accumulated amount in 4 years if the total sum becomes 1326 rupees?

(a) ₹ 1080 (b) ₹ 1120 (c) ₹ 918 (d) ₹ 750

5. A borrowed ₹960 from B at an annual simple interest rate of 6%, with the condition that the loan will be repaid over the next 4 yearly installments. In the first 3 installments, A will pay only one-fourth of the principal each year. In the final (4th) installment, A will pay the remaining principal along with the total interest accrued over the 4 years. Find the total amount A will pay at the end of the 4th year.

6. If the total simple interest on a principal amount at an annual rate of \(x\%\) for \(y\) years is \(\frac{pyx}{25}\) rupees, then the principal amount will be:

(a) \(2p\) rupees (b) \(4p\) rupees (c) \(\cfrac{p}{2}\) rupees (d) \(\cfrac{p}{4}\) rupees

7. Here's the English translation of your sentence: Calculate the compound interest and the total amount on ₹2,400 for 1½ years at an annual compound interest rate of 10%, compounded semi-annually.

8. If the interest on a certain amount of money at an annual rate of 5% for 8 years is ₹246 more than the interest at an annual rate of 7% for 4 years, what is the principal amount?

(a) ₹ 5020 (b) ₹ 2000 (c) ₹ 2050 (d) ₹ 2005

9. If the interest accrued on a certain principal amount at an annual rate of 8% over 6 years is ₹144, then what is the principal amount?

(a) ₹ 1440 (b) ₹ 450 (c) ₹ 444 (d) ₹ 300

10. If the total simple interest for 5 years is \(\cfrac{1}{5}\) of the principal, determine the annual simple interest rate.

(a) 4% (b) 5% (c) 10% (d) 25%

11. If the ratio of the principal to the total amount (principal + interest) in one year is \(4:9\), determine the annual simple interest rate.

12. At an annual simple interest rate of \(x\%\), if the total interest on a principal amount for \(y\) years is \(\cfrac{xyz}{25}\) rupees, then the principal amount is –

(a) ₹ 2z (b) ₹ 4z (c) \(\cfrac{z}{2}\) (d) \(\cfrac{z}{4}\)

13. At an annual interest rate of 4%, the difference between the simple interest and compound interest on a principal amount for 2 years is 40 rupees. Determine the principal amount.

14. If the total interest for 5 years is \(\cfrac{1}{5}\) of the principal, determine the annual interest rate.

(a) 4% (b) 5% (c) 10% (d) 25%

15. What would be the annual simple interest rate (percentage) if the interest for 4 years on a certain amount is \(\cfrac{8}{25}\) of the principal?

16. I have ₹5000. I deposited this amount in a bank at an annual compound interest rate of 8.5%. Write the calculation to determine the total amount (principal + interest) I will receive after 2 years.

17. 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?

18. At an annual compound interest rate of \( r\% \), the total compound amount on ₹\( p \) over 3 years is: \[ p \left(1 + \frac{r}{100}\right)^3 \]

(a) \(r\left(1+\cfrac{p}{100}\right)^3\) (b) \(3\left(1+\cfrac{r}{100}\right)^p\) (c) \(p\left(1+\cfrac{r}{100}\right)^3\) (d) \(p\left(1+\cfrac{r}{100}\right)^2\)

19. At an annual simple interest rate of \(x\%\), if the interest on a principal in \(x\) years is \(x\) rupees, then the amount of the principal is –

(a) \(x\) rupees (b) \(100x\) rupees (c) \(\cfrac{100}{x}\) rupees (d) \(\cfrac{100}{x^2}\) rupees

20. At an annual simple interest rate of \(x\%\), if the interest on a principal amount for \(x\) years is \(x\) rupees, what is the principal amount?

(a) \(x\) rupees (b) \(100x\) rupees (c) \(\cfrac{100}{x}\) rupees (d) \(\cfrac{100}{x^2}\) rupees

21. 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%

22. At what annual percentage rate of interest will the interest on an amount in 4 years become \(\cfrac{1}{6}\) of the total amount?

(a) 4% (b) 5% (c) 6% (d) 8%

23. If the ratio of the principal to its total amount after one year is 25:28, then the annual interest rate is—?

(a) 3% (b) 12% (c) 10\(\frac{5}{7}\)% (d) 8%

24. ₹1200 is lent at an annual interest rate of 6\(\frac{1}{4}\)% and ₹1000 is lent at an annual interest rate of 4\(\frac{1}{3}\)% on the same day. After how much time will the amounts (principal + interest) of both loans become equal?

(a) 20 years (b) 24 years (c) 15 years (d) 30 years

25. A certain amount of money amounts to ₹700 in 4 years at simple annual interest, and during this time the interest is 40% of the principal. What is the amount of the principal?

(a) ₹ 500 (b) ₹ 400 (c) ₹ 600 (d) ₹ 300

26. 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

27. Some money becomes 5 times its original amount in 5 years at simple interest. At the same rate of interest, the time required for that principal to become 17 times is:

(a) 17 years (b) 20 years (c) 18 years (d) 19 years

28. A person deposited ₹100 in a bank, and after 2 years received ₹121 as the total amount under compound interest. What is the annual percentage rate of compound interest?

29. Uday Babu lent a certain amount of money to one person at an annual simple interest rate of 4% for 4 years, and twice that amount to another person at an annual simple interest rate of 10% for the same duration. He received ₹960 more interest from the second person than from the first. Find the total amount of money Uday Babu lent.

30. Bimal Babu lent a certain amount of money to one person at an annual simple interest rate of 8% for 4 years, and twice that amount to another person at an annual simple interest rate of 10% for the same duration. Bimal Babu received ₹960 more interest from the second person than from the first. Find the total amount of money Bimal Babu lent.