# Compound Interest - Aptitude Questions and Answers

Compound Interest - Aptitude Questions and Answers for beginners to crake the interview aptitude questions on component interest

**Aptitude questions and answers for Compound Interest**

1) What is the **compound interest** on Rs. 2500 for 2 years at a rate of interest of 4% per annum?

- Rs. 180
- Rs. 204
- Rs. 210
- Rs. 220

The Correct answer is B

Explanation:

Principal (P) = Rs. 2500

Rate of interest(r) = 4%

Time (t) = 2 years

Compound Interest = Amount - Principal

2) What is the amount for a sum of money Rs.7500 at a 6% rate of interest C.I. for 2 years?

- Rs. 8427
- Rs. 8417
- Rs. 8400
- Rs. 8390

The Correct answer is A

Explanation:

Principal = Rs. 7500

r = 6%

t = 2 years

3) Ramesh borrowed Rs. 3600 at a certain rate of interest C.I. and the sum grows to Rs. 4624 in 2 years. What is the rate of interest?

- 12.3%
- 13.3%
- 14.3%
- 15.3%

The Correct answer is (B)

Explanation:

Principal = Rs. 3600

Amount = Rs. 4624

t = 2 years

We have;

4) On a certain sum of money the compound interest Rs. 318 is earned in 2 years. If the rate of interest is 12%, what is the principal amount?

- Rs. 1250
- Rs.1300
- Rs. 1200
- Rs. 1150

The Correct answer is A

Explanation:

We have;

C.I. = Rs. 318

r = 12%

t = 2 years

5) The simple interest on a certain sum of money at the rate of interest of 5% per annum for 2 years is Rs. 500. What is the compound interest on the same sum for the same period and at the same rate of interest?

- Rs.412.5
- Rs.400
- Rs.500
- Rs.512.5

The Correct answer is D

Explanation:

S.I. = 500

r = 5%

t = 2 years

Before finding C.I. we have to find the sum or principal;

Apply formula; Principal =

Principal = = Rs. 5000

Now we have to find the Amount;

Apply formula; Amount =

Amount = 5000

= 5000 * 1.05 * 1.05 = Rs. 5512.5

C.I. = Amount - Principal

C.I. = 5512.5 - 5000 = Rs. 512.5

6) In how many years the compound interest on Rs. 10000 at the rate of 10% will be Rs. 2100?

- 1.5 years
- 2 years
- 2.5 years
- 3 years

The Correct answer is B

Explanation:

Principal = Rs. 10000

r = 10%

C.I. = Rs. 2100

7) The difference between Simple Interest and Compound Interest on a certain sum of money for 2 years is Rs.200. If the rate of interest is 12 %, what is the sum?

- Rs. 11800
- Rs. 12000
- Rs. 12800
- Rs. 13000

The Correct answer is C

Explanation:

If the difference between the C.I. and S.I. on a certain sum of money for 2 years at a rate of interest r % is Rs. X, then the sum is given by;

Sum = X

We have;

X = Rs. 200

t = 2 years

r = 12

Therefore, Sum = 200

= 200 *

= 200 * *

= 200 * 64

= Rs. 12800 (Option C)

8) If the difference between Simple Interest and Compound Interest on a sum of money for 3 years is Rs. 200 and the rate of interest is 10%, what is the sum?

- Rs. 6451.6
- Rs. 6351.6
- Rs. 6251.6
- Rs. 6151.6

The Correct answer is A

Explanation:

If the difference between C.I. and S.I. on a certain sum for 3 years at a rate of interest r% is Rs. X, then the sum is given by;

Sum =

We have;

X = Rs. 200

r = 10%

Therefore, sum =

9) The difference between simple interest and compound interest on a sum of money for 1 year at 4% per 6 months is 4, what is the sum?

- Rs. 2100
- Rs. 2300
- Rs. 2500
- Rs. 3000

The Correct answer is C

Explanation:

Let the sum = Rs. X

t = 1 year = 2 half years (6 months)

r = 4% for 6 months

10) On lending a certain sum of money on C.I. one gets Rs.9050 in 2 years and Rs.9500 in 3 years. What is the rate of interest?

- 5%
- 4.5%
- 5.5 %
- 6%

The Correct answer is A

Explanation:

Amount after 3 years = Rs. 9500

Amount after 2 years = Rs. 9050

Interest of one year= 9500 - 9050 = 450

t = 1 year

Solution 2: Quicker Method

Apply formula: Rate of interest(r):

Y= Rs. 9500

X = 9050