Question

Find the rate of interest when Rs 800 fetches Rs 130 as a simple interest in 2 years 6 months.

Answer 1

Here,

$P=Rs800$

$T=2$ years $6$ months $=2\frac{6}{12}$ years

$=2\frac{1}{2}$ years $=\frac{5}{2}$ years

Hence,

$R=\frac{I\times 100}{P\times T}=\frac{130\times 100}{800\times \frac{5}{2}}\%$ p.a.

On simplification, we get,

$R=\frac{130\times 100\times 2}{800\times 5}\%$ p.a.

$=\frac{130\times 2}{40}\%$ p.a.

$=6.5\%$ p.a.

Therefore, the required rate of interest is $6.5\%$ p.a.