Question

Find the time in which $₨800$ will earn an interest of $₨120$ at $5\%$ p.a.

Answer 1

Given:

Principal $=₨800$

Rate of Interest $=5\%$ p.a

Simple interest $=₨120$

Let Time$=\mathrm{T}$years

We know that

Simple interest $=\frac{\mathrm{P}\times \mathrm{R}\times \mathrm{T}}{100}$

Then,

$120=\frac{800\times 5\times \mathrm{T}}{100}$
$$\begin{gathered} \Rightarrow \mathrm{T}=\frac{120\times 100}{800\times 5} \\ \Rightarrow \mathrm{T}=\frac{120}{40} \\ \Rightarrow \mathrm{T}=3 \end{gathered}$$

Hence, the time in which $₨800$ will earn an interest of $₨120$ at $5\%$ p.a. is $3$ years.