# If the simple interest on Rs. 1 for 1 month is 1 paisa, then the rate percent per annum will be ?

A. 10% B. 8% C. 12% D. 6% Answer: Option C
$\begin{array}{l} \mathrm{t}=1 \text { month }=\frac{1}{12} \text { year } \\ \mathrm{SI}=1 \text { paisa }=\text { Rs. } \frac{1}{100} \\ \mathrm{r} \%=\frac{\mathrm{SI} \times 100}{\mathrm{P} \times \mathrm{T}}=\frac{1 \times 100 \times 12}{100 \times 1 \times 1} \\ \mathrm{r} \%=12 \% \end{array}$