This is an addition problem because Molly and Natalie are putting their pencils together, and they will have more once they put all the pencils together. 

We can start at \(\displaystyle 13\) and count up \(\displaystyle 4\).

\(\displaystyle 13,14,15,16,17\)

\(\displaystyle \frac{\begin{array}[b]{r}13\\ +\ 4\end{array}}{ \ \ \space 17}\)

This is an addition problem because Tracy has two groups of strawberries that she is putting together into one group. When you put things together you are adding. 

We can start at \(\displaystyle 5\) and count up \(\displaystyle 7\).

\(\displaystyle 5,6,7,8,9,10,11,12\)

\(\displaystyle \frac{\begin{array}[b]{r}5\\ +\ 7\end{array}}{ \ \space 12}\)

This is an addition problem because we want to know the total number of pieces of chocolate that Zack ate, we are putting the pieces together that he had at lunch and after dinner. When we put things together we are adding. 

We can start at \(\displaystyle 3\) and count up \(\displaystyle 4\).

\(\displaystyle 3,4,5,6,7\)

\(\displaystyle \frac{\begin{array}[b]{r}3\\ +\ 4\end{array}}{ \ \ \ \space 7}\)

This is an addition problem because we are putting the red bals and the black balls together. When we put things together we are adding. 

We can start at \(\displaystyle 3\) and count up \(\displaystyle 16\).

\(\displaystyle 3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19\)

\(\displaystyle \frac{\begin{array}[b]{r}3\\ +\ 16\end{array}}{ \ \ \ \space 19}\)

This is an addition problem because we are putting the shirts and the shorts together. When we put things together we are adding. 

We can start at \(\displaystyle 6\) and count up \(\displaystyle 7\).

\(\displaystyle 6,7,8,9,10,11,12,13\)

\(\displaystyle \frac{\begin{array}[b]{r}6\\ +\ 7\end{array}}{ \ \ \ \space 13}\)

This is an addition problem because we are putting the leaves that Jeff collected in the front yard together with the leaves he collected in the backyard. When we put things together we are adding. 

We can start at \(\displaystyle 13\) and count up \(\displaystyle 6\).

\(\displaystyle 13,14,15,16,17,18,19\)

\(\displaystyle \frac{\begin{array}[b]{r}13\\ +\ 6\end{array}}{ \ \ \space 19}\)

This is an addition problem because Tim and Tom are putting their coins together. When we put things together we are adding. 

We can start at \(\displaystyle 11\) and count up \(\displaystyle 6\).

\(\displaystyle 11,12,13,14,15,16,17\)

\(\displaystyle \frac{\begin{array}[b]{r}11\\ +\ 6\end{array}}{ \ \ \space 17}\)

This is an addition problem because we are putting the table and chairs together. When we put things together we are adding. 

We can start at \(\displaystyle 6\) and count up \(\displaystyle 12\).

\(\displaystyle 6,7,8,9,10,11,12,13,14,15,16,17,18\)

\(\displaystyle \frac{\begin{array}[b]{r}6\\ +\ 12\end{array}}{ \ \ \ \space 18}\)

This is an addition problem because we are putting the blue and the yellow gumballs together. When we put things together we are adding. 

We can start at \(\displaystyle 14\) and count up \(\displaystyle 5\).

\(\displaystyle 14,15,16,17,18,19\)

\(\displaystyle \frac{\begin{array}[b]{r}14\\ +\ 5\end{array}}{ \ \ \space 19}\)

This is an addition problem because we are putting the hot pink flowers and the light pink flowers together. When we put things together we are adding. 

We can start at \(\displaystyle 9\) and count up \(\displaystyle 4\).

\(\displaystyle 9,10,11,12,13\)

\(\displaystyle \frac{\begin{array}[b]{r}9\\ +\ 4\end{array}}{ \ \ \space 13}\)