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What is the highest number that can be got from 4383 by moving exactly 2 matches?

Number 1 has got 2 matches, so I thought it will be 47831 as I remove two matches from second number (3), but it isn't the highest possible.

Format is same like this (1 is only number with only two matches)

image of 4383 with match-sticks

Does anybody know solution?

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Please do not use [homework] as a sole tag. Surely you know from which class you took the exercise, so please add the topic as a tag of the question. –  Asaf Karagila Jul 4 '11 at 11:51
    
edited .... can you help now? –  genesis Jul 4 '11 at 11:53
    
I felt that (puzzle) is the most appropriate tag, so I added it. If this really is homework, then you are having fun at school! –  Jyrki Lahtonen Jul 4 '11 at 12:02
6  
$438^3 = 84027672$? Or isn't that allowed? –  yatima2975 Jul 5 '11 at 10:41
2  
@ShreevatsaR: you can put the lower two matches on top, as the 'normal' and the superscripted 3 overlap. –  yatima2975 Jul 5 '11 at 15:15

3 Answers 3

up vote 2 down vote accepted

If you want to play with notation, you could have 4^783 or $438^3$ depending on what you allow.

      _   _  _
  |_| _| |_| _|
    | _| |_| _|

         _   _  _
  |_| /\  | |_| _|
    |     | |_| _|

Of course with actual matches, the caret would be squished in between the 4 and the 3. Might be considered cheating because really you should move the whole 4, as I did in the drawing. On the other hand:

             _
      _   _  _|
  |_| _| |_| _|
    | _| |_| 

Only moves 2 matches and would be how you would write $438^3 = 84,027,672$

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I am guessing 71393. Rotate the horizontal match of the leading 4 to split it into two ones, and grab one out of the 8 to turn the leading 1 into a 7.

      _   _  _
  |_| _| |_| _|
    | _| |_| _|

 _    _   _  _
  | | _| |_| _|
  | | _|  _| _|
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7^983 is the highest number. The 4 changes to a 7, and the 3 changes to a 9.

      _   _  _
  |_| _| |_| _|
    | _| |_| _|
      _   _  _
   _ |_| |_| _|
    | _| |_| _|
    |
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1  
That's even better :) –  yatima2975 Jul 5 '11 at 15:04
    
+1 It took me a while to see how you did it, but I got it in the end. Well done! –  Jyrki Lahtonen Jul 5 '11 at 19:16

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