The Fencing Problem.

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The Problem

A farmer has exactly 1000 metres of fencing and wants to fence off a plot of level land. She is concerned about the shape of the plot, but must have a perimeter of 1000m. So it could be

400m                                                        50m

                                                                           

                                    450m                          

1000m

Or anything else with a perimeter (or circumference) of 100m. She wishes to fence of the plot, which contains the maximum area. Investigate the shape, or shapes that could be used to fence in the maximum area using exactly 1000 metres of fencing each time.

I am going to investigate different with shapes with the perimeter of 1000 m to find out the maximum area. I will start with rectangles as they have drawn some rectangles already. Then I will try Isosceles triangle and equilateral triangle. Then I will do some regular polygons. The I will try a circle.

Rectangle and Square

I have drawn a table of different lengths and widths that give a perimeter of 1000m.

 The formula I used to calculate the area of the rectangles was L X W

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 I noticed from the graph the largest area was given by the rectangle, which is a square. So therefore there is no need to test this shape separately. The length and width of this shape is 250m by 250 m which is 62500

I then used my i.c.t skills to plot a graph between the relationship between width and area in order for me to find the maximum area within the rectangles. As you can see, the graph has formed a parabola.

Triangles

Isosceles triangle

Nest I drew a table for Isosceles triangle. I have ...

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