The question has a problem. The problem is that the increase is not linear and that makes it hard to answer. %s work best when studying linear conditions. This is not impossible to do. You just need to use some interval.
So for example, set up a small table up to 5
x f(x)
0 8
1 9.6
2 11.52
3 13.824
4 16.588
5 19.91
Low let's see what the % increase is from point 4 to point 5
16.588 * x/100 = 19.91
Multiply by 100
16.588 * x = 19.91 * 100
16.588 * x = 1991 Divide by 16.588
x = 1991/16.588
x = 120%
I think that may be the answer you seek. No matter what two consecutive points you pick, the answer will be 120%
If the points are not consecutive you will get a different answer than 120.
Answer: 120% But read the question's answer
