# A farmer wishes to build a large rectangular grazing area of dimensions, width (W) and length (L) splitting the area into 5 equal fields by dividing the width into 5 equal pieces. The total area of...

A farmer wishes to build a large rectangular grazing area of dimensions, width (W) and length (L) splitting the area into 5 equal fields by dividing the width into 5 equal pieces. The total area of all the fields must be 10500 square feet. Find the dimensions that use the least amount of fencing.

(It is not always the case that the width is shorter than the length. Round-off your answers to 3 decimal places)

Width W=

Length L=

mathsworkmusic | Certified Educator

calendarEducator since 2012

starTop subjects are Math, Science, and Business

We have that the perimeter of the field is given by

`P= 6l +2w`

and that the area is given by

`A = lw = 10500`

Notice the symmetry of the problem. The perimeter will be maximised when

`6l = 2w`

`implies` `w = 3l`

Therefore we have that

`A = 3l^2 = 10500`

`implies` `l = sqrt(10500/3) = 59.161` ft

Then `w = 3l = 3(59.16) = 177.482` ft

The length of the field should be 59.161 ft

The total width of the field should be 177.482 ft

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## Related Questions

lemjay | Certified Educator

calendarEducator since 2012

starTop subjects are Math and Science

The formula of area of rectangle is:

`A= Le n g t h* Width`

The given total area of the rectangular grazing lot is 10500 square feet. Its length is represented by L and width by W. So,

`10500=LW`

Solving for W yields:

`W=...

(The entire section contains 2 answers and 323 words.)