-(x-20)
Basically it’s the same as your other question but your not adding twenty!
Answer:
39.25 cubic feet of paint will be needed by Ellis.
Step-by-step explanation:
Volume of a cylinder:
The volume of a cylinder of radius r and height h is given by:

How much paint will Ellis need to paint all the surfaces of the 10 fenceposts?
This is the combined volume of these 10 fenceposts.
They are each 5 feet tall and have a diameter of 1 foot.
Radius is half the diameter, so
. Also 
10 fenceposts:
Each has the same volume, so:

39.25 cubic feet of paint will be needed by Ellis.
989.75060139
100.023424234 divided by 10.32342 = 9.68898138737
9.68898138737 + 1000.293920 = 1009.98290139
1009.98290139 - 20.2323 = 989.75060139