# Alipta got some amount of money from her father. In how many years will the ratio of the money and the interest obtained from it be 10 : 3 at 6% simple interest per annum ?

A. 7 years B. 3 years C. 5 years D. 4 years Answer: Option C
Let Principal and simple Interest is; $\begin{array}{l}=10x,3x\\ \text{ and time is }=t\\ \Rightarrow3x=\frac{10x\times6\times t}{100}\\ \Rightarrow t=\text{ 5 years }\end{array}$