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* * * * * 2 votes

Four numbers equals two dozen


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15 replies to this topic

#1 bonanova

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Posted 12 June 2014 - 09:29 AM

I'll give you four numbers and you give me two dozen.
You can use + - * and / and ( and ) as often as you like.
 
I was going to give you 2, 2, 8, 8,  but it occurs to me that (2 + 2) * 8 - 8 = 24 is not challenging.
 
So instead I'll give you 3, 3, 8, 8.
 
Have fun!
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The greatest challenge to any thinker is stating the problem in a way that will allow a solution.
- Bertrand Russell

#2 Pickett

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Posted 12 June 2014 - 07:14 PM

Spoiler for Super cheating way...

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#3 Pickett

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Posted 12 June 2014 - 07:21 PM

Spoiler for Or even more cheating:


Edited by Pickett, 12 June 2014 - 07:21 PM.

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#4 bonanova

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Posted 13 June 2014 - 06:46 AM

I have to say I like the first one.  ;)  But the puzzle is still open.


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

#5 m00li

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Posted 14 June 2014 - 07:22 AM

Spoiler for the smart aleck way


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#6 bonanova

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Posted 15 June 2014 - 08:14 AM

This one is challenging, but does have an answer.
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The greatest challenge to any thinker is stating the problem in a way that will allow a solution.
- Bertrand Russell

#7 DeGe

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Posted 16 June 2014 - 03:10 PM

Spoiler for Possibility


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#8 plasmid

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Posted 16 June 2014 - 03:12 PM

Spoiler for more shenanigans

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#9 Perhaps check it again

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Posted 16 June 2014 - 04:48 PM

A little more care has to be taken when presenting puzzles like this.

 

Instructions need to made as explicit as possible.

 

In this (original) puzzle, you are supposed to be told that you must use both of the

threes and both of the eights, but no other digits.  And you must use them in their original

orientation.  For example, you cannot flip a "3" around and meld it to a second "3" to form an "8." 

 

Concatenation, for example forming "33," should not be used unless stated.

 

You can choose only from some combination of addition, subtraction, division, and

multiplication.  (An aside:  Is the "-" permissible as a negative sign?)  And unlimited use of

parentheses is allowed.  Notice how parentheses may be used for grouping and/or multiplication,

depending on the circumstances of their placement in a given expression.

 

Any of those alleged solutions in this thread that made use of the square root don't count,

because that is not one of the four basic operations listed above.

 

Spoiler for - - - Here is a common form of the solution:

 

 

Unfortunately/fortunately, it is relatively easy to google this problem and find

multiple sites with the solution.


Edited by Perhaps check it again, 16 June 2014 - 04:50 PM.

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#10 bonanova

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Posted 18 June 2014 - 06:38 AM

Pcia:

Board Guideline 6 suggests being positive. If you find a puzzle not to your liking, try another. Authors are free to compose flavor text to suit their own particular style. Your kid sister can type the word Google. Most puzzle books have an answer section. Not really the point of buying the book, tho, is it? Please consider the reason you joined this site. And do read the posting guidelines. Thanks.
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The greatest challenge to any thinker is stating the problem in a way that will allow a solution.
- Bertrand Russell




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