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Nabu's Knee-knockerNabu's Knee-knocker



Background

Perhaps you know that the largest (in area) rectangle with perimeter 120 meters is a square with 30 meter sides. The area is 900 square meters (m2).

You can check the area of other rectangles with perimeter 120 meters.



So, if you have 120 meters of fencing to build a rectangular pen and you want the pen to have as large an area as possible, you'd make a square pen with 30 meter sides.


Problems

Suppose you have 120 meters of fencing and want to build two congruent rectangular pens with one side in common. Congruent means the rectangular pens look exactly alike. The picture shows an example.

Also, suppose you want the total area to be as large as possible. What dimensions do you make the rectangular pens?


  1. Consider the same problem for making three or four rectangular pens with 120 meters of fencing.


    What dimensions do you make the rectangular pens?


  2. Can you describe how to build several rectangular pens (any number) with 120 meters of fencing and with as large a total area as possible?



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Hint

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Solution