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8th Graders olimpyad problem


Best Answer plasmid, 15 August 2014 - 02:47 AM

Spoiler for one that the kids might be able to find with pencil and paper


Edit: Out of curiosity, what sort of time and resources do the kids get to solve these problems? Go to the full post


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#1 Barcallica

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Posted 13 August 2014 - 08:31 AM

This is a problem presented in local math olimpyad,

 

N(12,34)=12131415.....31323334

 

Find a, b, c, d where ab+cd=99 and N(ab,cd) is dividable by abcd (4 digit number).


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#2 bonanova

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Posted 13 August 2014 - 11:14 AM

Spoiler for how about


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The greatest challenge to any thinker is stating the problem in a way that will allow a solution.
- Bertrand Russell

#3 Barcallica

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Posted 14 August 2014 - 03:11 AM

Spoiler for how about

 

Yes that works :thumbsup: . But are there other answers as well? (Should have thought about 49.50 before posting :duh: )


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#4 Quantum.Mechanic

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Posted 14 August 2014 - 04:00 PM

I wrote a program to check.

Spoiler for Anyone want to verify these?


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#5 Quantum.Mechanic

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Posted 14 August 2014 - 04:04 PM

Testing a few targets other than 99,

Spoiler for it seems that

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#6 plasmid

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Posted 15 August 2014 - 02:47 AM   Best Answer

Spoiler for one that the kids might be able to find with pencil and paper


Edit: Out of curiosity, what sort of time and resources do the kids get to solve these problems?

Edited by plasmid, 15 August 2014 - 02:51 AM.

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#7 Barcallica

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Posted 15 August 2014 - 08:36 AM

Spoiler for one that the kids might be able to find with pencil and paper


Edit: Out of curiosity, what sort of time and resources do the kids get to solve these problems?

 

 

Usually 45 minutes per problem with pen, paper, ruler, compasses. Rarely they accept calculater and/or formula book.

 

But state olimpyad is 90 minutes per problem, 3 problems, 2 day. I once sat 9 hours straight coz I was challengin in above grade too.


Edited by Barcallica, 15 August 2014 - 08:37 AM.

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#8 DeGe

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Posted 15 August 2014 - 05:45 PM

I am adding this using my mobile and I don't see any spoiler button, so the mod may please put this in a spoiler.
Here is a general method to solve for more possibilities

 

Spoiler for Spoiler added by request


Edited by bonanova, 17 August 2014 - 06:28 PM.
Added spoiler

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