Question

Peter invested an amount of Rs. 12,000 at the rate of 10 % p.a. simple interest and. another amount at the rate of 20 % p.a. simple interest. The total interest earned at the end of one year on the total amount invested became 14 % p.a. Find the total amount invested.

• A. $Rs.20,000$
• B. $Rs.22,000$
• C. $Rs.24,000$
• D. $Rs.25,000$

Answer 1

The correct option is A $Rs.20,000$

Let the second amount $=x$

$\Rightarrow \frac{12000\times 10\times 1}{100}+\frac{x\times 20\times 1}{100}=\frac{(12000+x)\times 14\times 1}{100}$

$\Rightarrow \frac{120000}{100}+\frac{20x}{100}=\frac{168000+14x}{100}$

$\Rightarrow 120000+20x=168000+14x$

$\Rightarrow 20x-14x=168000-120000$

$\Rightarrow 6x=48000$

$\Rightarrow x=8000$

Hence total amount invested=$12000+8000=20000Rs.$