Question

A man borrowed some money from the bank at $10\%$ per annum simple interest for $5$ years. He paid back $Rs.36000$ to the bank and settled the account. What sum did he borrow from the bank?

Answer 1

Let the sum he borrowed be $Rs.x$

Rate of interest $=10\%$

Time $=5$ years

Amount $=Rs.36000$ [Money returned by the man with interest]
We know that the simple interest is given by

Simple Interest, $S.I=\frac{P\times R\times T}{100}$

$=\frac{x\times 10\times 5}{100}$

Amount can be calculated by

Amount $=$ Principal (Sum) $+$ Simple Interest

We can write like this

$\Rightarrow x+\frac{x\times 10\times 5}{100}=36000$

$\Rightarrow x+\frac{x}{2}=36000$

$\Rightarrow \frac{3x}{2}=36000$

$\Rightarrow x=\frac{36000\times 2}{3}$

$\therefore x=24000$
Hence, the amount he borrowed was $Rs.24000.$