Question

A person invested some amount at the rate of $12$% simple interest and some other amount at $10$% of simple interest and received yearly interest of $Rs.70$, but if he interchanged the amount invested, he would have received $Rs.3$ more as interest. Find the amounts invested

• A. $Rs.200,Rs.460$
• B. $Rs.360,Rs.240$
• C. $Rs.250,Rs.400$
• D. None

Answer 1

Answer: (C)

$Rs.250,Rs.400$

Let one amount invested be Rs $x$ and in another be Rs $y$.
As per the given statements, " $=>0.12x+0.1y=70$ --- (1)
And, $0.1x+0.12y=73$ --- (2)

Multiplying equation $\left(1\right)$ with $0.1$ we get, $0.012x+0.01y=7$ ----- equation $\left(3\right)$

Multiplying equation $\left(2\right)$ with $0.12$ we get, $0.012x+0.0144y=8.76$ ----- equation $\left(4\right)$

Subtracting equation $\left(3\right)$ from $\left(4\right)$, we get $0.0044x=1.76=>y=400$

Substituting $y=400$ in the equation $\left(1\right)$, we get $0.12\left(x\right)+0.1\left(400\right)=70=>x=250$

Hence, amount invested are Rs $250$ and in B is Rs $400$