Clumsy Planets

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Phlembac Adib Hasan
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Clumsy Planets

Unread post by Phlembac Adib Hasan » Thu Oct 25, 2012 9:19 am

On each planet of a star system, there is an astronomer observing the nearest planet. The number of planets is odd and pairwisely distances between them are different. Prove that at least one planet is not under observation.
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zadid xcalibured
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Re: Clumsy Planets

Unread post by zadid xcalibured » Thu Oct 25, 2012 6:58 pm

Hint:
Use induction.Look at the smallest (extreme) length.And notice that we need exactly n observers to observe all n planets.

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Phlembac Adib Hasan
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Re: Clumsy Planets

Unread post by Phlembac Adib Hasan » Fri Oct 26, 2012 11:17 am

I myself did it using contradiction.
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