If a certain sum of money becomes thrice of itself in 7 years 3 months at simple interest, then what will be the annual rate of interest?

Correct option is D

Given:
Principal (P) = 100
Time = 7 years 3 months = 7.25 years
Amount (A) = 3P = 300
Formula Used:
​$$SI = \frac{P \times R \times T}{100}$$​​
Solution:
Simple Interest (SI) = A – P = 300 – 100 = 200
​$$200 = \frac{100 \times R \times 7.25}{100} \\200 = 7.25R \\R = \frac{200}{7.25} \\R = 27.59\% \ (\text{approx.})$$​​