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# Four numbers equals two dozen

## Question

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!

## Recommended Posts

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(8 / 8) * (3 / 3) = 12/12

Voila! Two dozens!

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Flip a 3 around (ε) and butt it up against the other 3 to make an 8...then it's just 8 + 8 + 8 = 24!

Edited by Pickett
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I have to say I like the first one. But the puzzle is still open.

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3*8

you never mentioned all 4 had to be used
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This one is challenging, but does have an answer.

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(3+3) * square root (8+8)

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3*3+8+8 = 25 = 12+13

One regular dozen and one baker's dozen

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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.

8/(3 - 8/3) . . . . . . Answer

= 8/(9/3 - 8/3)

= 8/(1/3)

= 8*3

= 24

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

multiple sites with the solution.

Edited by Perhaps check it again
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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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(3+3) * square root (8+8)

Creative. But sqrt is not available.

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3*3+8+8 = 25 = 12+13One regular dozen and one baker's dozen

Cute. Honorable mention.

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bonanova, please spell out my username when addressing me. For several seconds at first, I didn't know what "Pcia" was.

Yes, so Board Guideline 6 suggests being positive, and I was. I was positive, thorough, accurate, honest, assertive,

and to the point.

Don't mistake my style for not being positive.

No, I don't agree with you. Don't speak for me. One of the main points for me *is* the answer section

of the puzzle book. I don't trust the author to know what he or she to know what the answer is without

the alleged solution given in the back. I'm looking for errors in the answers. I'm looking for missing

additional solutions (and I don't mean typos).

I'm looking for errors such as faulty wording in the statements of the original problems.

I don't have to consider at all the reasons (See? They are plural?) why I joined this site. I have total

confidence in my background of decades of exposure to various puzzles and certain branches of mathematics

and the challenge of new puzzles that I encounter here, just as a for instance.

I see you repeated to a user from my own post what he/she couldn't use for his/her solution.

And "Thanks" back at you.

Edited by Perhaps check it again
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Perhaps check it again:

Don't sweat the acronym thing, I don't know how long you've been around, but I've been around on and off for years and bon-chan (my nickname for bonanova ) has been around even longer, and it's a very common practice to use acronyms, so common we sometimes take it for granted .

Tone is something that's pretty subjective in text (I've been a victim of having mine misread myself), so I can't tell for sure where your post was negative or not, but I think it's generally considered bad form to criticize someone's puzzle. Like bon-chan said, there are plenty of puzzles here, and if you don't particularly care for one, you can simply move on to another more to your taste.

As a puzzle maker myself, I think the thing you have to understand is that many puzzle designers put a lot of time and thought into designing puzzles, and it doesn't seem very nice when someone puts down something that you spent effort for to provide to them for free :/.

And for better or for worse, posting an answer you found online or already know kinda ruins it for people who were trying to come up with the answer on their own.

Puzzle makers and puzzle solvers have a symbiotic relationship, and, seeing how activity on BrainDen has been falling off lately, I would encourage everyone to try to minimize activities and/or attitudes that would discourage either .

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Perhaps check it again:

Don't sweat the acronym thing,

**No, you can decide for yourself not to "sweat it," but I'll stick to my own convictions.**

I don't know how long you've been around, but I've been around on and off for years and bon-chan (my nickname for bonanova )

has been around even longer, and it's a very common practice to use acronyms, so common we sometimes take it for granted .

** But I don't use them for others. I take the time to spell out the usernames.**

Tone is something that's pretty subjective in text (I've been a victim of having mine misread myself),

so I can't tell for sure where your post was negative or not, but I think it's generally considered bad form

to criticize someone's puzzle. Like bon-chan said, there are plenty of puzzles here, and if you don't

particularly care for one, you can simply move on to another more to your taste.

**No, I think it's "bad form" for someone not to speak up and not get someone on the right track.

Nip it in the bud early, and not be afraid to walk on eggs. And avoid having users give posts with that don't

count with needless replies from the OP with clarifications, because the proble/puzzle was presented as

well as it could have been. Stop being politically correct about avoiding hurt feelings and hurt egos

of the puzzle presenter. Puzzle presenter, state a thank you for the input and be grateful.**

As a puzzle maker myself, I think the thing you have to understand is that many puzzle designers put a lot of time

and thought into designing puzzles, and it doesn't seem very nice when someone puts down something that you

** That puzzle, at least what was supposed to be the complete puzzle, was not designed by the

presenter in this forum. No, you have the wrong perception and attitude. It was being corrected, and

the presenter needed to have shown gratitude. There needed to have been, "Thank you, Perhaps check it again.

I will make the amendment." Or some other similar statement could have been made. Again, it comes down

to the puzzle presenter checking his/her ego.**

And for better or for worse, posting an answer you found online or already know kinda ruins it for people who were

trying to come up with the answer on their own.

** And this statement doesn't count, because my answer was hidden. It was stated as an answer and was hidden

by a spoiler.**

Puzzle makers and puzzle solvers have a symbiotic relationship, and, seeing how activity on BrainDen has been

falling off lately, I would encourage everyone to try to minimize activities and/or attitudes that would discourage either .

**You are preaching to the choir.**

Edited by Perhaps check it again
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Thanx everyone for an interesting debate.

I wish real life were also as clear as pcia wants the op to be. I won't check it again, perhaps.

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