Question

The difference between $SI$ and $CI$ of a certain sum of money is $Rs.48$ at $20\%$ p.a. for $2$ years. Find the principal

Answer 1

$CP=P[{(1+\frac{r}{100})}^n-1]=P[{(1+\frac{20}{100})}^2-1]$

$CP=P\left[\left(\frac{36-25}{25}\right)\right]=\frac{11P}{25}$

$SI=\frac{P\times 20\times 2}{100}=\frac{11P}{5}$

$CI-SI\Rightarrow 48=\frac{11P}{25}-\frac{2P}{5}$

$P=25\times 48=1200$