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Points on a circle


Best Answer bubbled, 06 May 2014 - 05:47 AM

Spoiler for My take

Go to the full post


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16 replies to this topic

#1 bonanova

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Posted 02 May 2014 - 10:28 AM

What is the probability that n points placed at random on the circumference of a circle all lie on a semicircular arc?

That is, for at least one of the points, all the others lie [0, pi] radians from it.


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The greatest challenge to any thinker is stating the problem in a way that will allow a solution.
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#2 DeGe

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Posted 02 May 2014 - 04:45 PM

Spoiler for Points

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#3 Rob_G

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Posted 02 May 2014 - 07:13 PM

Spoiler for Points

 

 

Spoiler for I have to disagree
 


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#4 Rob_G

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Posted 02 May 2014 - 07:53 PM

Spoiler for I wanna say

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#5 m00li

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Posted 03 May 2014 - 08:17 AM

Spoiler for complex


The 'aha' solution you are looking for might not be applicable for a sphere. am i right?


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#6 plasmid

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Posted 03 May 2014 - 03:28 PM

m00li: if you start with points 0 and x and then add a third point y that is within a semicircle containing 0 and x but y is not between 0 and x, then the probability of another point being in a semicircle with all three of those is no longer 1-x/2pi but is 1-(longest distance between any of 0 x and y)/2pi


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#7 m00li

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Posted 04 May 2014 - 06:48 AM

Yes, the solution is absolutely incorrect
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#8 DeGe

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Posted 04 May 2014 - 09:44 PM

Spoiler for Slight change


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#9 bonanova

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Posted 05 May 2014 - 12:58 AM

Spoiler for Slight change

 

What if you picked a different starting point?


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#10 bubbled

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Posted 06 May 2014 - 05:47 AM   Best Answer

Spoiler for My take


Edited by bubbled, 06 May 2014 - 05:52 AM.

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