Ellis is painting wooden fenceposts before putting them in his yard. They are each 5 feet tall and have a diameter of 1 foot. There are 10 fenceposts in all. How much paint will Ellis need to paint all the surfaces of the 10 fenceposts? Use 3.14 for π, and round your answer to the nearest hundredth. Provide an explanation and proof for your answer to receive full credit.

Respuesta :


Step-by-step explanation:

height of fence post 5 ft

diameter of fence post = 1 ft radius = 0.5 ft

Total surface of the fence post = 2pir(r+h)

= 2* 3.14 *(5+0.5)

= 6.28 * 5.5

= 34.54 ft^2 / post

For 10

345.4 ft^2

How much paint /ft^2

Answer:

Step-by-step explanation:

Comment

The first step is to find the surface area of 1 fence post.

The formula is

Area_ends = 2 pi r^2 for the ends.

Area_body = 2*pi*r * h

Givens

r = d/2          r is the radius ; d is the diameter

r = 1/2 foot

h = 10 feet

Solution

1 fence post

Area = ends + area body

Area =  2*3.14 * (1/2)^2 + 2 * pi * r * h

Area = 2*3.14* (1/2)^2 + 2 * 3.14 * 1/2 * 10

Area = 1.57 + 31.4

Area = 32,97 square feet.

10 fence posts

10*32.97 = 329.7 square feet

Answer

10 fence posts have 329.7 square feet in area.