1. Some money amounts to 944 rupees in 3 years at simple interest. If the annual rate of interest increases by 25%, then the same money amounts to 980 rupees in the same time. Find the rate of interest and the principal.

2. If the annual simple interest rate increases from 4% to 5%, causing a person's income to rise by ₹1000, then the person's principal amount is _____.

(a) ₹ 4000 (b) ₹ 5000 (c) ₹ 10000 (d) ₹ 50000

3. If the annual simple interest rate increases from 4% to 5%, causing a person's income to rise by ₹1000, then the person's principal amount is _____.

(a) ₹ 4000 (b) ₹ 5000 (c) ₹ 10000 (d) ₹ 50000

4. A certain sum of money amounts to ₹944 in 3 years at simple interest. If the rate of interest is increased by 25%, the same sum amounts to ₹980 in the same time period. Find the principal amount and the original rate of interest.

5. Due to the decrease in the annual simple interest rate from 4% to 3\(\frac{3}{4}\)%, a person's annual income decreases by 60 rupees. What is the principal amount of that person?

6. If the interest rate increases by 2%, how much principal amount will result in an additional interest of 300 rupees over 5 years?

(a) ₹ 2000 (b) ₹ 3000 (c) ₹ 4000 (d) ₹ 3600

7. Due to the annual simple interest rate decreasing from 6% to 5\(\frac{1}{2}\)%, a person's annual income decreased by 75 rupees. How much money had they deposited in the bank?

8. The annual simple interest rate decreases from \( 4\% \) to \( 3\frac{3}{4}\% \), causing a person's yearly income to reduce by 60 rupees. Find the principal amount of that person.

9. My aunt wants to will ₹56,000 between her two sons, aged 13 and 15, in such a way that by the time each turns 18, the total amount (principal + interest) received by both sons is equal. The interest is calculated at an annual simple interest rate of 10%. Determine how much should be allotted to each son in the will.

10. If the annual simple interest rate decreases from 5.5% to 4.5%, and a person's yearly interest income is reduced by ₹250 as a result, what is the principal amount?

11. At an annual simple interest rate of 6%, the interest for 5 months is \(\cfrac{x}{10}\) rupees. What will the principal be?

(a) ₹ 2x (b) ₹ 4x (c) ₹ 10x (d) ₹ 20x

12. What should be the annual simple interest rate so that the principal increases by 75% in 6 years?

(a) 8% (b) 20% (c) 12.5% (d) 15%

13. Due to a decrease in the annual simple interest rate from \(4\%\) to \(3\frac{3}{4}\%\), a person's annual income is reduced by ₹600. Find that person's principal (capital).

14. If the ratio of a certain principal amount to its compound amount after a certain period is 15:21 and the annual simple interest rate is 5%, then the duration of time is –

(a) 4 years (b) 2 years (c) 8 years (d) 10 years

15. Ishan deposits 1000 rupees on the first day of each month in a monthly savings scheme. If the annual simple interest rate is 5%, how much will Ishan receive, including interest, at the end of 9 months?

16. 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.

17. Due to the annual simple interest rate decreasing from 4% to 3\(\frac{3}{4}\)%, a person's annual income decreases by ₹60. What is that person's principal amount?

18. At an annual simple interest rate of \(r\%\), the interest on 100 rupees for 1 year is \(\cfrac{r}{100}\) times the principal.

19. 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?