Question

What sum will amount to Rs. 4000 in 3 years at 6% p.a. compound interest?

Answer 1

Answer:

Compound Interest=764.064

Explanation:

1st year

SI=P*R*T/100

=4000*6*1/100

=240

Amount=4240

2nd year

SI=P*R*T/100

=4240*6*1/100

=254.4

Amount=4494.4

3rd year

SI=P*R*T/100

=4494.4*6*1/100

=269.664

Amount=4764.064

CI=Amount-Principal

=4764.064-4000

=764.064

: )

Answer 2

Given:

Amount=Rs.4,000

Years=3

Interest rate=6% p.a.

To find:

The principal amount

Solution:

The required amount is Rs.3,358.5.

We can obtain the amount of principal by using the following formula for determining the compound interest.

Let the principal's value be P.

Using the formula,

The amount=Principal's value×$(1+rate/100)^{years}$

We will substitute the given values to obtain P.

4,000=P×$(1+6/100)^{3}$

4000=P×106/100×106/100×106/100

4000×$100^{3}$=$106^{3}$ ×P

4,00,00,00,000/$106^{3}$ =P

4,00,00,00,000/106×106×106=P

4,00,00,00,000/11,91,016=P

On dividing,

3358.47=P

So, P=Rs.3,358.5.

Therefore, the required amount is Rs.3,358.5.