# On a certain sum the simple interest for $12 \frac{1}{2}$ year is $\frac{3}{4}$ of the sum. Then the rate of interest is?

A. 5% per year B. 6% per year C. 7% per year D. 8% per year Answer: Option B
$\begin{array}{l} \text { Let sum }=x \\ \begin{array}{l} \text { Interest }=\frac{3}{4} x \\ \text { Interest }=\frac{\text { PTR }}{100} \\ \Rightarrow \frac{3}{4} x=\frac{x \times \mathrm{R} \times 12.5}{100} \\ \mathrm{R}=6 \% \end{array} \end{array}$