Question

2] Neha invested Rs. 9000 at the rate
of 10 p.c.p.a in a scheme for 2years.
find the amount she gets after 2
years if the interest is compounded
annually.​

Answer 1

Given:

• Principal = Rs. 9000

• Time = 2 years

• Rate = 10 %

What To Find:

We have to find the compound interest annually.

Formula:

$\rm 1. \: Amount = Principal \bigg( 1 + \dfrac{R}{100} \bigg)^{Time}$

$\rm 2. \: Compound \: Interest = Amount - Principal$

Solution:

• Finding the amount.

Using the formula,

$\rm \implies \: Amount = Principal \bigg( 1 + \dfrac{R}{100} \bigg)^{Time}$

Substitute the values,

$\rm \implies \: Amount = 9000 \bigg( 1 + \dfrac{10}{100} \bigg)^{2}$

Solve the brackets,

$\rm \implies \: Amount = 9000 \bigg( \dfrac{110}{100} \bigg)^{2}$

Remove the brackets,

$\rm \implies \: Amount = 9000 \times \dfrac{110}{100} \times \dfrac{110}{100}$

Cancel the zeros,

$\rm \implies \: Amount = 9 \times 110 \times 11$

Multiply the numbers,

$\rm \implies \: Amount = Rs. \: 10890$'

• Finding the Compound Interest.

Using the formula,

$\rm \implies \: Compound \: Interest = Amount - Principal$

Substitute the values,

$\rm \implies \: Compound \: Interest = Rs. \: 10890 - Rs. \: 9000$

Subtract the values,

$\rm \implies \: Compound \: Interest = Rs. \: 1890$

∴ Therefore, the compound interest is Rs. 1890.

Answer 2

Given:

Principal = Rs. 9000

Time = 2 years

Rate = 10 %

What To Find:

We have to find the compound interest annually.

Formula:

$\rm 1. \: Amount = Principal \bigg( 1 + \dfrac{R}{100} \bigg)^{Time}$

$\rm 2. \: Compound \: Interest = Amount - Principal$

Solution:

Finding the amount.

Using the formula,

$\rm \implies \: Amount = Principal \bigg( 1 + \dfrac{R}{100} \bigg)^{Time}$

Substitute the values,

$\rm \implies \: Amount = 9000 \bigg( 1 + \dfrac{10}{100} \bigg)^{2}$

Solve the brackets,

$\rm \implies \: Amount = 9000 \bigg( \dfrac{110}{100} \bigg)^{2}$

Remove the brackets,

$\rm \implies \: Amount = 9000 \times \dfrac{110}{100} \times \dfrac{110}{100}$

Cancel the zeros,

$\rm \implies \: Amount = 9 \times 110 \times 11$

Multiply the numbers,

$\rm \implies \: Amount = Rs. \: 10890$'

Finding the Compound Interest.

Using the formula,

$\rm \implies \: Compound \: Interest = Amount - Principal$

Substitute the values,

$\rm \implies \: Compound \: Interest = Rs. \: 10890 - Rs. \: 9000$

Subtract the values,

$\rm \implies \: Compound \: Interest = Rs. \: 1890$

∴ Therefore, the compound interest is Rs. 1890.