Question

Rupees 4000 amount to Rs. 5000 in 8 years: in what time will Rs. 2100 amount to Rs. 2800 at the same rate?

Answer 1

In first case:
A= Rs. 5000
P=Rs.4000
I=A-P
=Rs. 5000 -Rs. 4000
=Rs. 1000
T=8 years
$R=\frac{100\times I}{P\times R}$
$=\frac{100\times 1000}{4000\times 8}$
$=\frac{25}{8}$ %
In the second case:
A=Rs. 2800
P=Rs. 2100
I= Rs. 2800-Rs. 2100=Rs. 700
R=$\frac{25}{8}$ % \( T= \frac{100 \times I}{P \times R}= \frac{100 \times 700}{2100 \times \frac{25}{8} \) $=\frac{100\times 700\times 8}{2100\times 25}=\frac{32}{3}years=10\frac{2}{3}years$ $=10\frac{2}{3}\times 12months=10\frac{24}{3}months$
=10 years 8 months