Question

Find the rate at which a sum becomes $\frac{6}{5}$ times of itself in 4 years.

• A. 5%
• B. 4%
• C. 10%
• D. 8%

Answer 1

The correct option is A 5%

Let the sum invested be ₹ x.
So, the amount = ₹ 1.2x.

We know that,
Principal + Interest = Amount.
So, the interest earned = ₹ (1.2x - x) = ₹ 0.2x.

The Simple Interest earned on a sum of ₹ P for a period of T years at the rate of R% p.a S.I is given by $\frac{P\times R\times T}{100}$.

So, $0.2x=\frac{x\times R\times 4}{100}$
Hence, the rate of interest = R% = 5% p.a.