Practice Geometric Optimization in Math

Use these practice problems to test your method after reviewing the concept explanation and worked examples.

Quick Recap

Finding the best geometric configuration โ€” the shape that maximizes area, minimizes perimeter, uses the least material, or achieves some other optimal outcome โ€” subject to given constraints.

What rectangle with fixed perimeter has the most area? A square!

Showing a random 20 of 50 problems.

Example 1

medium
A field with perimeter 8080 m must be rectangular. If one side is constrained to be at least 2525 m, find the dimensions maximizing area.

Example 2

easy
Two rectangles have the same perimeter of 2424 cm: one is 8ร—48 \times 4 cm and one is 6ร—66 \times 6 cm. Which has greater area? Does this match the P2/16P^2/16 maximum?

Example 3

hard
A poster has total area 384384 cm2^2 with 44 cm margins on top and bottom and 22 cm margins on the sides. What dimensions of the poster maximize the printable area?

Example 4

medium
A rectangle is inscribed under the curve y=4โˆ’x2y = 4 - x^2 on the xx-axis, with its base on the axis. What is the maximum area?

Example 5

easy
Of all shapes enclosing a fixed area, which has the smallest perimeter?

Example 6

challenge
Among all triangles inscribed in a circle of radius 11, find the one with maximum area and give that area.

Example 7

easy
Of all rectangles with perimeter 4040 inches, what is the smallest possible area (assuming positive sides)?

Example 8

easy
Of all rectangles with a fixed perimeter, which shape has the most area?

Example 9

easy
True or false: among all closed curves of length LL, the circle encloses the largest area.

Example 10

easy
A rectangle has perimeter P=40P = 40 cm. Using the formula maximum area =P2/16= P^2/16, compute the maximum area and the dimensions of the optimal rectangle.

Example 11

medium
A farmer builds a rectangular pen against a straight wall (no fence needed on the wall side) with 40 m of fence. What dimensions maximize area?

Example 12

hard
A cylindrical can is open at the top and must hold V=500V = 500 cm3^3. What radius minimizes the material (lateral + base)?

Example 13

hard
An open-top box has a square base of side xx and height hh. If the total surface area equals 4848 cm2^2, what is the maximum volume?

Example 14

easy
To use the least fencing for a fixed rectangular area, what proportions should the rectangle have?

Example 15

medium
A farmer has 40 m of fence for a rectangular pen. What dimensions maximize the area, and what is that area?

Example 16

easy
Using Amaxโก=P2/16A_{\max} = P^2/16, find the maximum area of a rectangle with perimeter P=24P = 24.

Example 17

hard
Find the rectangle of maximum area inscribed in the ellipse x2a2+y2b2=1\dfrac{x^2}{a^2} + \dfrac{y^2}{b^2} = 1 with sides parallel to the axes.

Example 18

hard
Find the largest area of an isoceles triangle inscribed in a circle of radius 11.

Example 19

medium
A square and a circle have the same perimeter PP. Which has the larger area, and by what ratio?

Example 20

challenge
Among all rectangles inscribed in a semicircle of radius 1 (base on the diameter), what is the maximum area?