All about flooble | fun stuff | Get a free chatterbox | Free JavaScript | Avatars    
perplexus dot info

Home > Shapes > Geometry
Square in a Pentagon (Posted on 2013-12-01) Difficulty: 3 of 5
What is the size of the largest square which can fit inside a regular pentagon with a side-length of 1?

No Solution Yet Submitted by Danish Ahmed Khan    
Rating: 3.0000 (1 votes)

Comments: ( Back to comment list | You must be logged in to post comments.)
Solution More likely to be correct solution. | Comment 2 of 4 |
I should have tried putting a corner of the square into a corner of the pentagon.  The problem this time is I have the square standing up straight.   This is an improvement but not the best yet.

The height of the pentagon is sin(72)+sin(36)
if you divide this by the √2 diagonal of the square you get
.25(√(5+√5)+√(5-√5))≈1.0881

You can improve this by rotating the square by 9º
(divide by cos(9º))
≈ 1.1017

  Posted by Jer on 2013-12-02 16:15:39
Please log in:
Login:
Password:
Remember me:
Sign up! | Forgot password


Search:
Search body:
Forums (0)
Newest Problems
Random Problem
FAQ | About This Site
Site Statistics
New Comments (13)
Unsolved Problems
Top Rated Problems
This month's top
Most Commented On

Chatterbox:
Copyright © 2002 - 2024 by Animus Pactum Consulting. All rights reserved. Privacy Information