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Origins of Tetris?


Best Answer bushindo, 07 February 2013 - 10:49 PM

Prove that you cannot
cover a 10 x 10 chessboard with 25 figures
attachicon.gifTfig.gif

(Problem from Russian Math Olympiads. 6-th grade, 1964.)

 

Answer

Spoiler for

Go to the full post


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3 replies to this topic

#1 Prime

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Posted 07 February 2013 - 09:03 PM

Prove that you cannot
cover a 10 x 10 chessboard with 25 figures

Tfig.gif


(Problem from Russian Math Olympiads. 6-th grade, 1964.)


  • 0

Past prime, actually.


#2 bushindo

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Posted 07 February 2013 - 10:49 PM   Best Answer

Prove that you cannot
cover a 10 x 10 chessboard with 25 figures
attachicon.gifTfig.gif

(Problem from Russian Math Olympiads. 6-th grade, 1964.)

 

Answer

Spoiler for


  • 2

#3 k-man

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Posted 07 February 2013 - 10:58 PM

Prove that you cannot
cover a 10 x 10 chessboard with 25 figures
attachicon.gifTfig.gif

(Problem from Russian Math Olympiads. 6-th grade, 1964.)

 

Answer

Spoiler for

Nice! I had a proof that involved reviewing different scenarios, but I'm not going to post it as it's not as elegant as this.


Edited by k-man, 07 February 2013 - 11:04 PM.

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#4 Prime

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Posted 07 February 2013 - 11:23 PM

Answer

Spoiler for

Yes, that's the solution.

Spoiler for or you could put it like that:

I knew, this problem would not last long here.


Edited by Prime, 07 February 2013 - 11:32 PM.

  • 0

Past prime, actually.





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