A number when multiplied by 13 is increased by 180. The number is :

Answer: Option C

Let the number be x
Then,
$$\begin{array}{rl}& \Rightarrow 13x=x+180\\ & \Rightarrow 12x=180\\ & \Rightarrow x=\frac{180}{12}\\ & \Rightarrow x=15\end{array}$$