Question

Find the Rate of Interest if the interest on $₨600$ for $5$ years is $₨150$.

Answer 1

Given:

Principal $=₨600$

Simple interest $=₨150$

Time$=5$years

Let Rate of Interest $=\mathrm{R}\%$ p.a

We know that

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

Then,

$150=\frac{600\times \mathrm{R}\times 5}{100}$
$$\begin{gathered} \Rightarrow \mathrm{R}=\frac{150\times 100}{600\times 5} \\ \Rightarrow \mathrm{R}=\frac{100}{20} \\ \Rightarrow \mathrm{R}=5 \end{gathered}$$

Hence, the required interest rate is $5\%$.