Question

A sum amounts of Rs. 2652 in 6 years at 5% p.a simple interest .
Find : (i) The sum
(ii) the time in which the same sum will double itself at the same rate of interest.

Answer 1

$\left(i\right)$

Here, $A=Rs.2652,T=6years,R=5\%$

$\Rightarrow$ $A=P\left(\frac{100+TR}{100}\right)$

$\therefore$ $P=\frac{A\times 100}{100+TR}$

$\therefore$ $P=\frac{2652\times 100}{100+6\times 5}$

$\therefore$ $P=\frac{2652\times 100}{130}$

$\therefore$ $P=Rs.2040$

$\left(ii\right)$

Here, $P=Rs.2040,A=4080,R=5\%$

$\Rightarrow$ $I=A-P=Rs.4080-Rs.2040=Rs.2040$

$\Rightarrow$ $I=\frac{PRT}{100}$

$\Rightarrow$ $T=\frac{I\times 100}{PR}$

$\therefore$ $T=\frac{2040\times 100}{2040\times 5}$

$\therefore$ $T=20years$