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Geometry problem for the mathletes (not a joke this time)

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pokerfan Donating Member (1000+ posts) Send PM | Profile | Ignore Mon Feb-04-08 07:32 PM
Original message
Geometry problem for the mathletes (not a joke this time)
I like to call this the irrigation problem. You have a section of land (one mile square). Or maybe it's cutting identical circles from a square pf cloth or plywood.

Anyway, what is the diameter of the largest circles in each of the following arrangements:



The solutions for n=1 and n=4 are trivial. The n=2 configuration has been posted here before.

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Duer 157099 Donating Member (1000+ posts) Send PM | Profile | Ignore Mon Feb-04-08 07:51 PM
Response to Original message
1. Huh? I must be a mathtard
I don't even understand the question
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pokerfan Donating Member (1000+ posts) Send PM | Profile | Ignore Mon Feb-04-08 08:04 PM
Response to Reply #1
2. Possilbe I didn't phrase it the best
If the square is 1x1, then what is the diameter of the circles in each of the six pictures.

For one circle, it's obviously 1.
For four circles, it's obviously 0.5.

The others are not so trivial, but answers exist.

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Ptah Donating Member (1000+ posts) Send PM | Profile | Ignore Mon Feb-04-08 08:31 PM
Response to Original message
3. I think I've got the three circles in a square.
S=2R+2*sin(75)

if sin(75)=.966 and r=1 then

S=3.932*R

R=.254*S






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pokerfan Donating Member (1000+ posts) Send PM | Profile | Ignore Mon Feb-04-08 08:48 PM
Response to Reply #3
4. correct
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pokerfan Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Feb-05-08 02:56 PM
Response to Original message
5. ANSWERS
m=1: 1

n=2:

n=3:

n=4: 0.5

n=5:

n=6:





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Ptah Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Feb-05-08 03:13 PM
Response to Reply #5
6. ?
Edited on Tue Feb-05-08 03:20 PM by Ptah
4/(4+SQRT(2)+SQRT(6))=.508


Edit. I was thinking radius, you answered with diameter.

:blush:



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pokerfan Donating Member (1000+ posts) Send PM | Profile | Ignore Tue Feb-05-08 03:59 PM
Response to Reply #6
7. Complete article
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