Question

Nadeem invested a sum of ₹15000 in two schemes, one at rate of interest of 5% p.a. and the other at a rate of 7.5% p.a. If the interest on both is the same, find the money he deposited in each scheme.

Answer 1

Let amount deposited in first scheme be A and in the second scheme be B.
Given, A + B = ₹15000 ---- (i)
Also, we know that,

$\frac{\mathrm{Interest}}{\mathrm{Principal}}=\frac{\mathrm{Rate}}{100}\Rightarrow \mathrm{Interest}=\frac{\mathrm{Principal}\times \mathrm{Rate}}{100}$
According to the question,
$\frac{A\times 5}{100}=\frac{B\times 7.5}{100}\Rightarrow A=1.5B-----\left(\mathrm{ii}\right)$
From equations (i) and (ii),
1.5B + B = 15000
$\Rightarrow 2.5B=15000\Rightarrow B=\frac{15000}{2.5}=6000\Rightarrow A=15000-6000=9000$
The amount deposited in first and second scheme are ₹9000 and ₹6000 respectively.