The simple interest received on a sum at the rate of 4 percent per annum is 3/5 of the sum. What is the time period?

Correct option is D

Given:
Rate of Interest (R) = 4% per annum
Simple Interest (SI) = $$\frac{3}{5} \times \text {Principal (P)}$$​​
Formula Used:
Simple Interest (SI) = $$\frac{P \times R \times T}{100}$$​​
Time (T) = $$\frac{SI \times 100}{P \times R}$$​​
Solution:
​$$T = \frac{\frac{3}{5} \times P \times 100}{P \times 4}\\\ \\T = \frac{3 \times 100}{5 \times 4}\\\ \\T = \frac{300}{20}\\$$​​
T = 15
Therefore, the time period is 15 years.