# Aptitude - Compound Interest

### Exercise :: Compound Interest - General Questions

6.

What will be the compound interest on a sum of Rs. 25,000 after 3 years at the rate of 12 p.c.p.a.?

 A. Rs. 9000.30 B. Rs. 9720 C. Rs. 10123.20 D. Rs. 10483.20 E. None of these

Explanation:

Amount
 = Rs. 25000 x 1 + 12 3 100
 = Rs. 25000 x 28 x 28 x 28 25 25 25
= Rs. 35123.20 C.I. = Rs. (35123.20 - 25000) = Rs. 10123.20

7.

At what rate of compound interest per annum will a sum of Rs. 1200 become Rs. 1348.32 in 2 years?

 A. 6% B. 6.5% C. 7% D. 7.5%

Explanation:

Let the rate be R% p.a.

 Then, 1200 x 1 + R 2 = 1348.32 100  1 + R 2 = 134832 = 11236 100 120000 10000  1 + R 2 = 106 2 100 100 1 + R = 106 100 100 R = 6%

8.

The least number of complete years in which a sum of money put out at 20% compound interest will be more than doubled is:

 A. 3 B. 4 C. 5 D. 6

Explanation:

 P 1 + 20 n > 2P  6 n > 2. 100 5

 Now, 6 x 6 x 6 x 6 > 2. 5 5 5 5

So, n = 4 years.

9.

Albert invested an amount of Rs. 8000 in a fixed deposit scheme for 2 years at compound interest rate 5 p.c.p.a. How much amount will Albert get on maturity of the fixed deposit?

 A. Rs. 8600 B. Rs. 8620 C. Rs. 8820 D. None of these

Explanation:

Amount
 = Rs. 8000 x 1 + 5 2 100
 = Rs. 8000 x 21 x 21 20 20
= Rs. 8820.

10.

The effective annual rate of interest corresponding to a nominal rate of 6% per annum payable half-yearly is:

 A. 6.06% B. 6.07% C. 6.08% D. 6.09%

Explanation:

 Amount of Rs. 100 for 1 year when compounded half-yearly = Rs. 100 x 1 + 3 2 = Rs. 106.09 100 Effective rate = (106.09 - 100)% = 6.09%