Question

Alex invested his savings in two parts. The simple interest earned on the first part at 15% per annum for 4 years is the same as the simple interest earned on the second part at 12% per annum for 3 years. Then, the percentage of his savings invested in the first part is

• A. 62.50%
• B. 37.50%
• C. 60%
• D. 40%

Answer 1

Answer: (B)

37.50%

Answer 2

The correct answer is B: 37.50%
Alex divided his savings into two parts: one invested at a 15% annual interest rate for 4 years, and the other invested at a 12% annual interest rate for 3 years.
Let's denote the amount invested in the first part as ₹x and in the second part as ₹y.
The interest earned from the first part is calculated as $0.15\times{x}\times4$, and the interest earned from the second part is calculated as $0.12\times{y}\times3$.
Equating these two interests:
$0.15\times{x}\times4=0.12\times{y}\times3$
Solving for x and y:
20x=12y
This implies the ratio of x to y is 3:5.
Therefore, the percentage of savings invested in the first part is $\frac{3}{(3+5)}=\frac{3}{8}=0.375$.
Converting this to a percentage gives us 37.5%.
So, Alex invested 37.5% of his savings in the first part.