Good Evening Friends,
What is the length of the sides for a 12 sided structure with an inscribed diameter of 12'?
Respectfully, :)
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Good Evening Friends,
What is the length of the sides for a 12 sided structure with an inscribed diameter of 12'?
Respectfully, :)
12 divided by 12 = 1
Hey Ralph
Good question. My answer is 2 7/8 but I am not telling you in which measurement system. Did you know the answer or just asking?
Regards from the sunny country
3.2154 feet. (or approx 3' 2 9/16")
Good Evening Friends,
Tonz was the closest to the correct answer as according to my square manual the inscribed diameter of 12' for a 12 sided structure is 3' 2 5/32".
The actual figure in the decimal column is .154 which is a little less than 5/32 so it is OK to round it off to 5/32".
Thank you for your support and I hope at least one person learned something.
Respectfully, :)
Well, what I learned is that it is a lot easier if you have a book with all the answers in it.:pQuote:
Originally Posted by Ralph Jones
Good Evening Bob,
I have the book that has the formulas in it but I still have to figure out the answer myself. I am more fortunate than a few as I have had this manual since I was thirteen when I started serving my apprenticeship under my grandfather and he made me to memorize most of the book.
Thank you for your support.
Respectfully, :)
This really is basic trigonometry and Ralph I'm afraid your maths is a little flawed.
Dia = 12' therefore Rad = 6'
12 Segments. 360/12 = 30 deg. Divide by 2 to get right angle triangle = 15 deg.
Internal angles for any right angle triangle = 180 deg.
Therefore missing angle = 180 - 90 - 15 = 75 deg
Half length X = 6 / Tan 75 deg = 1.6077'
X 2 for full length = 3.2154'
This equals 3' and 0.2154' which equals 3' and 2.585"
(So the decimal is 0.585" not 0.154" as Ralph states)
0.585" is approx 9/16 as stated previously....
or if you want to get really accurate (and a little pedantic :) ).
9/16 = .5625"
19/32 = .5938"
37/64 = .5781"
75/128 = .5859"
It looks like Ralph may be the one who has learned something today. :)