Quantitative Aptitude Questions and Answers section on “Compound Interest” with solution and explanation for competitive examinations such as CAT, MBA, SSC, Bank PO, Bank Clerical and other examinations.

# Compound Interest

The compound interest on Rs. 10000 in 2 years at 4% per annum, the interest being compounded half-yearly, is:

[A]Rs. 912.86

[B]Rs. 828.82

[C]Rs. 824.32

[D]Rs. 636.80

**Rs. 824.32**

Since Interest = 10824.3216 – 10000 = Rs.824.32

Hence option [C] is the right answer.

In what time will Rs. 1000 becomes Rs. 1331 at 10% per annum compounded annually?

[A]2 years

[B]3 years

[C]3.5 years

[D]2.5 years

**3 years**

Let the required time be n years, Then,

Hence option [B] is the right answer.

A sum becomes Rs. 1352 in 2 years at 4% per annum compound interest. The sum is :

[A]Rs. 1250

[B]Rs. 1270

[C]Rs. 1245

[D]Rs. 1225

**Rs. 1250**

Let the sum be Rs. x

Hence option [A] is the right answer.

In how may years will Rs. 2000 amounts to Rs. 2420 at 10% per annum compound interest?

[A]2.5 years

[B]1.5 years

[C]2 years

[D]3 years

**2 years**

According to question,

∴ t = 2 years

Hence option [C] is the right answer.

The principal, which will amount to Rs. 270.40 in 2 years at the rate of 4% per annum compound interest, is

[A]Rs. 220

[B]Rs. 250

[C]Rs. 225

[D]Rs. 200

**Rs. 250**

Let the principal be Rs.P.

Hence option [B] is the right answer.

The compound interest on Rs. 2000 in 2 years if the rate of interest is 4% per annum for the first year and 3% per annum for the second year, will be

[A]Rs. 143.40

[B]Rs. 140.40

[C]Rs. 141.40

[D]Rs. 142.40

**Rs. 142.40**

Hence option [D] is the right ansewr.

At what percent per annum will Rs. 3000/- amounts to Rs. 3993/- in 3 years if the interest is compounded annually?

[A]13%

[B]10%

[C]9%

[D]11%

**10%**

P = Rs. 3000 , A = Rs. 3993 , n = 3 years

Hence option [B] is the right ansewr.

The compound interest on Rs. 8,000 at 15% per annum for 2 years 4 months, compounded annually is :

[A]Rs. 3109

[B]Rs. 3091

[C]Rs. 2980

[D]Rs. 3100

**3109 Rs.**

∴ Compound Interest = Rs. (11109 – 8000) = Rs. 3109

Hence option [A] is the right ansewr.

A sum of money on compound interest amounts to Rs. 10648 in 3 years and Rs. 9680 in 2 years. The rate of interest per annum is :

[A]20%

[B]5%

[C]10%

[D]15%

**10%**

Let the sum be Rs. P and rate of interest be R% per annum. Then,

On dividing equation (2) by (1) :

Hence option [C] is the right ansewr.

At what rate per cent per annum will Rs. 2304 amount to Rs. 2500 in 2 years at compound interest?

[A]

[B]

[C]

[D]

Let the rate per cent per annum be r. Then,

Hence option [C] is the right ansewr.