Question

A person invested some amount at the rate of 12$\%$ simple interest and a certain amount at the rate of 10$\%$ simple interest. He received yearly interest of Rs 130. But if he had interchanged the amounts invested, he would have received Rs 4 more as interest. How much did he invest at 12$\%$ simple interest ?

• A. Rs 700
• B. Rs 500
• C. Rs 800
• D. Rs 400

Answer 1

Answer: (B)

Rs 500

Answer 2

Let amount invested at 12% be x and amount invested at
10% be y.
According to question
130 = $\frac{x × 12 × 1 }{100}$ + $\frac{y × 10 × 1}{100}$
$⇒$13000=12$x$ + 10y ……..(i)
And 134 = $\frac{x × 10 × 1 }{100}$ + $\frac{y × 12 × 1}{100}$
$⇒$13400=10$x$ + 12y ……..(ii)
From equations (i) and (ii)
$x$=500
So the correct option is (B).