Question

In what time, will the simple interest on a certain sum of money at $6\frac{1}{4}$% p.a be $\frac{3}{8}$ of the sum itself?

Answer 1

$sum=P+I$ $and$ $I=\frac{3}{8}sum$

$\therefore \frac{8I}{3}=P+I\Rightarrow P=\frac{5I}{3}$

$I+\frac{PTR}{100}$

$I=\left(\frac{5I}{3}\right)\left(T\right)\left(\frac{25}{4}\right)\times \frac{1}{100}$

$T=\frac{3\times 4\times 100}{5\times 25}years$

$=\frac{48}{5}years$

$T=9.6years.$