Question

what principal will amount to rs.560 in 3 years at 4 percent annum simple interst
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Answer 1

$\mathfrak{\large{\underline{\underline{Answer :-}}}}$

The Principal is Rs. 500

$\mathfrak{\large{\underline{\underline{Explanation :-}}}}$

Given :

Principal amounts to - Rs. 560

In - 3 Years

At - 4% per annum [Simple Interest]

To Find :

The Principal

Solution :

Consider the Principal as x

Simple Interest on the Principal =

$\longrightarrow$ Amount = Simple Interest + Principal

$\longrightarrow$ 560 = Simple Interest + x

$\longrightarrow$ Simple Interest = 560 - x

$\rule{300}{1.5}$

Here -

• Principal = x
• Time = 3 Years
• Rate = 4%
• Simple Interest = 560 - x

★ $\boxed{\sf{SI = \frac{Principal \times Rate \times Time}{100}}}$

$\tt{\longrightarrow} \: 560 - x = \dfrac{x \times 4 \times 3}{100}$

$\tt{\longrightarrow} \:560 - x = \dfrac{x \times 12}{100}$

$\tt{\longrightarrow} \:560 -x = \dfrac{12x}{100}$

$\tt{\longrightarrow} \:560 -x = \dfrac{ 3x}{25}$

$\tt{\longrightarrow} \:25(560 -x)= 3x$

$\tt{\longrightarrow} \:14000 -25 x= 3x$

$\tt{\longrightarrow} \: 25x + 3x= 14000$

$\tt{\longrightarrow} \:28x = 14000$

$\tt{\longrightarrow} \:x = \dfrac{14000}{28}$

$\tt{\longrightarrow} \:x = 500$

$\therefore$ The Principal is Rs. 500

Answer 2

$\mathfrak{\large{\underline{\underline{Answer :-}}}}$

$\mathfrak{\large{\underline{\underline{Explanation :-}}}}$

⟶ Amount = Simple Interest + Principal

⟶ 560 = Simple Interest + x

⟶ Simple Interest = 560 - x

★ $\boxed{\sf{SI = \frac{Principal \times Rate \times Time}{100}}}$

$\tt{\longrightarrow} \: 560 - x = \dfrac{x \times 4 \times 3}{100}$

$\tt{\longrightarrow} \:560 - x = \dfrac{x \times 12}{100}$

$\tt{\longrightarrow} \:560 -x = \dfrac{12x}{100}$

⟶25(560−x)=3x

⟶14000−25x=3x

⟶25x+3x=14000

⟶28x=14000

⟶x= 14000/28

⟶x=500

Therefore∴ The Principal is Rs. 500