Study the dot pattern below. 

1. Sketch the $4^{\text{th}}$ and $5^{\text{th}}$ figures.

   Hint (a):

   What is the pattern of the first $3$ figures? Follow this pattern in sketching Figures $4$ and $5$

   Answer (a):

   See Figures 4 and 5 below.

   $\begin{array}{c c c} \newcommand{blank}{\ } & \bullet \\ \newcommand{blank}{\ } & \bullet \\ \newcommand{blank}{\ } & \bullet \\ \newcommand{blank}{\ } & \bullet \\ \bullet & \newcommand{blank}{\ } & \bullet \\ \newcommand{blank}{\ } & \bullet \\ \newcommand{blank}{\ } & \bullet \\ \newcommand{blank}{\ } & \bullet \\ \newcommand{blank}{\ } & \bullet \end{array}\\ \text{Figure 4}$

   $\begin{array}{c c c} \newcommand{blank}{\ } & \bullet \\ \newcommand{blank}{\ } & \bullet \\ \newcommand{blank}{\ } & \bullet \\ \newcommand{blank}{\ } & \bullet \\ \newcommand{blank}{\ } & \bullet \\ \bullet & \newcommand{blank}{\ } & \bullet \\ \newcommand{blank}{\ } & \bullet \\ \newcommand{blank}{\ } & \bullet \\ \newcommand{blank}{\ } & \bullet \\ \newcommand{blank}{\ } & \bullet \\ \newcommand{blank}{\ } & \bullet \end{array}\\ \text{Figure 5}$

2. How many dots will the $50^{\text{th}}$ figure have?

   Hint (b):

   Try finding a way to describe how you add dots to the figures.
   How many dots did you start with? How many do you add each time?