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Area & Perimeter Design Challenge

Build fenced gardens on a grid and discover the surprising relationship between perimeter and area. Given a fixed fence length, can you find the shape that encloses the most space? Given a fixed garden size, can you use the least fencing?

Guided Experiment Fixed Fence Length

For a fixed perimeter (fence length), which rectangle shape do you think will enclose the most area?

Write your hypothesis in the Lab Report panel, then click Next.

Controls

You have exactly 16 units of fence. Build a garden that encloses the most area.

Hint Try a 4x4 square. Does any other shape do better?

Perimeter 16/16 units - constraint met!
4 units
120
4 units
120
Area score100% Optimal!

Current area 16 sq units (best 16)

Grid

each cell = 1 unit
444 × 4

Measurements

Area

16

sq units

Perimeter

16

units

Shape Analysis

Shape typeSquare
Aspect ratio1 : 1 (square)
Dimensions4 × 4

Constraint

Fixed perimeter 16 units of fence

Goal maximize area

Optimal 4 × 4 = 16 sq units

Data Table

(1 row)
#ChallengeWidth(units)Height(units)Area(sq units)Perimeter(units)Optimal?
1
0 / 500
0 / 500
0 / 500

Reference Guide

Area vs Perimeter

Area measures the space inside a shape (square units). Perimeter measures the total length of the boundary (units).

A=w×hA = w \times h
P=2(w+h)P = 2(w + h)

These two measures are related but independent. You can change one without the other staying the same.

Rectangles and Squares

For a rectangle with a fixed perimeter P, the area is maximized when width equals height. This is a square.

Amax⁡=(P4)2A_{\max} = \left(\frac{P}{4}\right)^2

Similarly, for a fixed area A, the perimeter is minimized by a square with side length equal to the square root of A.

Pmin⁡=4AP_{\min} = 4\sqrt{A}

Real-World Applications

Farmers and gardeners use this principle when deciding how to fence a plot. A square field gives the most growing area for a given length of fencing.

Architects apply the same idea when designing floor plans. Rooms that are close to square use less wall material for the same floor area.

Nature also follows this pattern. Cells, soap bubbles, and honeycombs all tend toward shapes that minimize surface area relative to volume.

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