A sum of money invested at simple interest becomes 17/10 of itself in 2 years and 6 months. What is the rate of interest per annum?

A. 22%

B. 16%

C. 28%

D. 34%

Answer: Option C

Solution(By Examveda Team)

$$\eqalign{ & {\text{S}}{\text{.I}}{\text{.}} = \frac{{P \times r \times t}}{{100}} \cr & 7 = \frac{{10 \times r \times 5}}{{2 \times 100}} \cr & r = 28\% \cr} $$