Answer:
3.5 works because 18-1.666 (2/3) X 3.5 = 12.169 which is less than 15.
4.5 works because 18-1.666 (2/3) X 4.5 = 10.503 which is also less than 15.
8.0 works because 18- 1.666 (2/3) X 8.0 = 4.672 which is also less than 15.
By looking at the number line included 4.5 is the only choice that is included in the shaded line part. So I think that that is the correct answer here.
Explanation:
Hope that this helps! :)
Have a great rest of your day/night!