Answer:
n = r - 2.5
Explanation:
We have the following data:
7 4.5
8 5.5
10 7.5
12 9.5
Now, what we will do is what happens if we subtract each one:
7 - 4.5 = 2.5
8 - 5.5 = 2.5
10 - 7.5 = 2.5
12 - 9.5 = 2.5
The difference is always kept constant, therefore the equation would be:
n = r - 2.5