Answer:
To find the average rate of change, we divide the change in the output value by the change in the input value.
Turn them both into mixed fractions and voila
Find the ticket unit cost: divide the total paid, $324, by the number of tickets, x. Then the form of the unit cost is
$324
--------- .
x
This question is highly unusual in that you write "x" as the number of tickets sold, instead of a specific number of tickets. Supposing that you'd sold 100 tickets for $324, then the unit cost would be, much more typically, a numeric ratio:
$324
----------------- = $3.24/ticket
100 tickets
Hello!
We can write this as a proportion below.

As you can see, 4 is eight times 0.5. Therefore, we can multiply eighteen by eight to get our answer.
18(8)=144
Just to check, we can cross multiply and divide.
72/0.5=144
Therefore, our answer is
144 feet.
I hope this helps!