Question

Find the sum which will amount to Rs 800 in
4 years at 25% P.a.​

Answer 1

Given:

• Principal = Rs. 800
• Rate = 25 %
• Time = 4 years

What To Find:

We have to find the amount.

How To Find:

To find the amount we will find

1. $\sf{Simple \: Interest = \dfrac{Principal \times Rate \times Time}{100}}$

2. Amount = Principal + Simple Interest

Solution:

• Finding the simple interest.

Using the formula,

⇒ $\sf{Simple \: Interest = \dfrac{Principal \times Rate \times Time}{100}}$

Substitute the values,

⇒ $\sf{Simple \: Interest = \dfrac{800 \times 25 \times 4}{100}}$

Cancel the zeros,

⇒ $\sf{Simple \: Interest = 8 \times 25 \times 4}$

Multiply the numbers,

⇒ Simple Interest = Rs. 800

• Finding the amount.

Using the formula,

⇒ Amount = Principal + Simple Interest

Substitute the values,

⇒ Amount = Rs. 800 + Rs. 800

Add the formula,

⇒ Amount = Rs. 1600

∴ Thus, the amount is Rs. 1600.

Answer 2

Step-by-step explanation:

Given :

Amount= principal + simple interestRate = 25%Time = 4 years Let the principal be y

Formula for simple interest is:

$\frac{principal \: x \: rate \: x \: time}{100} = simple \: interest$

$= > \frac{y \: x \: 25 \: x \: 4}{100} = 800 - y$

${cancellation \: process$

cancelling 25 by 100 which will result to 4.

Then 4/4 = 1

$y = 800 - y$

$y + y = 800$

$2y = 800$

$y = \frac{800}{2}$

$y = 400$

Therefore, sum is 400.

Hope it helps you.