Dhaka Junior 2011/1

Problem for Junior Group from Divisional Mathematical Olympiad will be solved here.
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Please don't post problems (by starting a topic) in the "Junior: Solved" forum. This forum is only for showcasing the problems for the convenience of the users. You can post the problems in the main Divisional Math Olympiad forum. Later we shall move that topic with proper formatting, and post in the resource section.
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Moon
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Dhaka Junior 2011/1

Unread post by Moon » Wed Feb 02, 2011 8:21 am

1. What is the minimum difference between a $12$ digit odd number and a $11$ digit even number?
"Inspiration is needed in geometry, just as much as in poetry." -- Aleksandr Pushkin

Please install LaTeX fonts in your PC for better looking equations,
learn how to write equations, and don't forget to read Forum Guide and Rules.

Mehfuj Zahir
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Re: Dhaka Junior 2011/1

Unread post by Mehfuj Zahir » Wed Feb 02, 2011 11:27 am

Differnce should be 3

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Moon
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Re: Dhaka Junior 2011/1

Unread post by Moon » Wed Feb 02, 2011 2:44 pm

Ok...What did we learn from the sentence "Differnce should be 3"? In divisional you can write this and probably get full point, but here our main goal is to discuss and learn. So PLEASE everyone post complete solution or at least some outline/logic, please.
"Inspiration is needed in geometry, just as much as in poetry." -- Aleksandr Pushkin

Please install LaTeX fonts in your PC for better looking equations,
learn how to write equations, and don't forget to read Forum Guide and Rules.

Mehfuj Zahir
Posts: 78
Joined: Thu Jan 20, 2011 10:46 am

Re: Dhaka Junior 2011/1

Unread post by Mehfuj Zahir » Wed Feb 02, 2011 3:08 pm

The minimum difference between a 12 digit odd 11& digit even number should be the difference between last 11digit even number and 1st 12 digit odd number.Thus we get 3

ataher.sams
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Re: Dhaka Junior 2011/1

Unread post by ataher.sams » Thu Dec 01, 2011 9:52 pm

I think that's r8.... ;)
Ataher Sams

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