Iron Works Worksheet #3 KEY

Name ______Date______

You will construct a round pen to work horses in. The diameter of the pen will be 90 feet. The height of the pen will be 6 feet tall with the bars spaced at 12 inch centers. You will put 6 bars in the fence including the top rail. Then you will plate the bottom 4 feet of the pen. (Steel plate comes in 4’X8’ pieces) The posts will be spaced on 10ft centers. The post will be 6 feet tall above ground and 2.5 feet below ground. The pen will need 12 inches of sand at time of completion. Use Pi = 3.14

  1. How many linear feet of pipe will be needed to go around the pen one time? _282.6 feet__

Pi times diameter

3.14 · 90’ = 282.6’

  1. How many linear feet will be needed to encircle the pen 6 times? __1695.6 linear feet_____

To find the linear feet take circumference times six

282.6’ · 6 = 1695.6 linear feet

  1. How many linear feet of steel plate will be needed to encircle the pen? ____282.6 feet______

Circumference equals linear feet

282.6’ = 282.6’

  1. How many steel plates will be needed to encircle the pen? _36 Steel Plates_

Linear feet divided by eight feet

282.6’ / 8’ = 36 steel plates

  1. How many square feet of steel plate will be used in this project? ____1130.4 square feet____

Linear feet times height of the plate

282.6’ · 4’ = 1130.4ft2

  1. What is the total length of one post? ____8.5 feet_____

Length above ground added to the length below the ground equals post length 2.5’ + 6’ =8.5’

  1. How many posts will be needed to go around the pen with 10 feet of distance from center to center? ____28 post_____

Circumference divided by the distance from center to center equals total posts needed

282.6’ / 10 = 28.26 = 28 post

  1. How many linear feet of post material will be needed to construct the posts? ____238 feet______

Length of post times number of posts equals linear feet of material 8.5’ · 28posts = 238’

  1. You call Johnny Longhaul Sand Company to bring sand out to fill your pen with 12 inches of sand. How many cubic feet of sand will he need to bring to achieve this goal? 6358.5 cubic feet_

Twelve inches equals one foot

12” = 1’

Pi times radius squared times height equals cubic units

3.14 · (45’)(45’) · 1 = 6358.5ft3

  1. You have this beautiful pen that does not have a gate, to install a gate you will need 10 extra feet of material that you have used for the bars to construct the gate. What is the final linear footage needed now? 1705.6’

Take the answer from #2 and add ten feet1695.6’ + 10’ = 1705.6’

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