ANSWER
36 feet
EXPLANATION
We are given that the scale of the model is 1 inch to 9 feet.
The two flagpoles are 4 inches apart in the model.
To find the distance between them when they are installed, we have to use ratio/proportion.
Let the distance between them be x.
We have that from the scale:
1 inch = 9 feet
=> 4 inches = x feet
Now, we can cross-multiply:
[tex]\begin{gathered} 1\cdot x=4\cdot9 \\ \Rightarrow x=36\text{ feet} \end{gathered}[/tex]
Therefore, the distance between them when they are installed is 36 feet.
