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10SIMPLE AND COMPOUND INTEREST

Q1. Calculate the simple interest and fill in the blanks in the table given below:

Principal Time Period Rate of interest Simple Interest

` 12000 514

years 12% per 6 months _________

` 29200 25 days 10% per annum _________` 750 18 months 6% per annum _________

Q2. Rahul and Riya deposited the same sum of money on simple interest at the same rate of interest. Rahul got ` 53,100 in 3 years whereas Riya got ` 58,500 in 5 years. Find the rate of interest and the sum of money invested.

Rate of interest = _________________

Sum of money invested = _________________

Q3. Find the compound interest, when a sum of ` 8000 is invested at 10% per annum for 2 years:

a. interest payable yearly

b. interest payable half–yearly

a. Interest payable yearly = _________________

b. Interest payable half–yearly = _________________

Q4. A sum P is deposited for T years at R% per annum rate of interest and the simple interest is calculated. In which of the following cases will the simple interest remain unchanged?

a. if Principal is doubled and time period is halved

b. if Rate of interest is calculated quarterly and time period is halved

c. if Rate of interest is calculated quarterly and time period is doubled

Answer: _________________

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Q5. A sum p is deposited for t years at r% rate of interest. When will the simple interest be equal to compound interest? Choose the correct option from the following:

a. At the end of the first year

b. If principal is doubled

c. At the end of the second year

d. If rate of interest is halved

Answer: _________________

Q6. At what rate per cent per annum will the compound interest on ` 3200 is ` 1032 in 2 years?

Rate = ____________

Q7. Rajat wants to buy a bicycle which costs ` 8,900. If he has ` 8000, which he deposits at 6% per annum compounded annually, will Rajat be able to buy the bicycle:

a. after 1 year?

b. after 2 years?

Choose the correct answer from the options given above.

Answer: _________________

Q8. After taking the medicine, Rajan’s platelets count is increasing by 50% per day. If the present platelets count is 12,000, find the platelets count after 3 days.

Answer: _________________

Q9. The price of a car depreciates by 12% of its value in the first year. In subsequent years the value is depreciated by 10%. If Rajat bought a car for ` 8,00,000, find the sale value of the car after 3 years.

Answer: _________________

Q10. A man borrowed ` 14,600 from a bank on 23rd April, 2016 at 5% p.a. How much simple interest did he pay on this money on 11th June, 2016?

Answer: _________________

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Answers

1. Principal Time Period Rate of interest Simple Interest

` 12000 514

years 12% per 6 months

` 15120

` 29200 25 days 10% per annum ` 200` 750 18 months 6% per annum ` 67.5

2. 6% per annum ; ` 45,000

3. a. ` 1680; ` 1724.05

4. (a)

5. (a)

6. 15% per annum

7. (b)

8. 40,500 platelets

9. ` 5,70,240

10. ` 100