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# Coins

## 84 posts in this topic

The problem doesn't mention that anyone is around. I would just keep my mouth shut, pick up and pocket all three coins.

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How about 'If I don't get the gold coin, I'll get nothing' ?

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But what if you said something like...there are three coins on the table and you will give me the gold coin????

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Gadzooks!! this is the first riddle I've gotten right the FIRST TIME!!! look out logic world, here I come!!

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They would just give you one coin, the least expensive one

That would REALLY be a paradox!

Assume you said "I will not get any coins".

If you then get any coin, you have been lying, and therefor deserve no coin. But not getting a coin would mean you told the truth and thus deserve to get a coin. Which brings you back to getting a coin for a lie, and so on, and so forth, ad infinitum.

But I've thought of two possible ideas:

1: Say "You won't give me anything but the gold coin".

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Now, IF they give you anything but the gold coin, you would have lied, and therefor deserve no coin at all.

And if they give you no coin at all, you had been saying the truth and thus deserved a coin.

The only way they can avoid paradox, is by giving you the gold coin.

2: Say "IF you give me ANY coin, it can ONLY be the gold one".

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This is actually the same statement in a somewhat different form. Thus it would result in exactly the same situation as above: they can ONLY give you the gold coin to avoid a conflict of terms.

Happy puzzling,

CollectingCoins.

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"There is a gold coin on the table; silver is another coin on the table; and copper is the last coin on the table."

Three true statements in one sentence. Each true statement gains you one coin, so you'll gain all three coins.

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I think the most effective sentence would be "You will give me the gold coin, or I will beat you to a bloody pulp".

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This is an easy one for simple thought. A true statement will get you the gold coin.. a false will get you none. Nothing is said about what the statement has to be about, only that you must be truthful. Lets assume the statement must concern the exercise...here is a garaunteed statement

"There are 3 coins on the table"

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well these make alot of sense when you read the answer but if you dont i would NEVER had thought of the answer so i have no idea but i do get it only when i read the answer

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I was trying to stump my girlfriend with this and she came up with a situation i believe works... does it??

If you give me a coin, then it will be the gold coin.

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I was trying to stump my girlfriend with this and she came up with a situation i believe works... does it??

If you give me a coin, then it will be the gold coin.

Doesn't work. The person in charge of giving out coins can easily declare that sentence false and say that if he would have given you a coin it would have been the copper one.

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One of the coins on the table is GOLD...

LOL

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THIS QUESTION WOULD WORK ONLY IF EVERYTHING IS CONSIDERED AS TRUE.....

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id say "there are 3 coins on the table", the solution just isnt that clear

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Columbus egg

If I pick up 3 coins i will finde a gold ;-)

Begining conditions are in wrong form.

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Columbus egg

If I pick up 3 coins i will finde a gold ;-)

Begining conditions are in wrong form.

what condition in particular is wrong?

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The two correct answers, both given on the first page, are

"You will give me neither the silver coin nor the copper coin."

and

"You will give me either the gold coin or nothing."

Note that these are exactly equivalent statements; saying one is the same thing as saying the other.

Let 'G', 'S', and 'C' represent the respective statements "You will give me the gold coin," "You will give me the silver coin," and "You will give me the copper coin." Then '!G', '!S', and '!C' represent the respective statements "You will not give me the gold coin," "You will not give me the silver coin," and "You will not give me the copper coin."

Using this notation, the first correct answer can be represented as

I. !S AND !C [or, equivalently, !(S OR C)]

while the second correct answer can be represented as

II. G OR (!G AND !S AND !C)

These two statements are exactly equivalent. For convenience, let's define N to mean "You will give me nothing" (i.e. N is !G AND !S AND !C). Then II, the second correct answer, can be written as

III. G OR N

This can be rewritten as

IV. (!S AND !C AND !N) OR (!G AND !S AND !C)

Since !S and !C are both common to both conditions, we can say

V. !S AND !C AND (!N OR !G)

Since N is (!G AND !S AND !C), then !N is (G OR S OR C). So we have

VI. !S AND !C AND (G OR S OR C OR !G)

Since we have already established !S AND !C as a condition, we can get rid of the possibility S OR C. This reduces to

VII. !S AND !C AND (G OR !G)

But (G OR !G) is a trivially true identity, so we can simply omit it (it's always true so it's like multiplying by one). So this becomes

VIII. !S AND !C

which is identical to I, the first correct answer.

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You ensure you get the gold coin, by getting all of them.

Just say the following sentences:

-The gold coin is the most valuble of the 3.

-The silver coin is less valuble than the gold.

-The copper coin is the least valuble coin.

All sentences are true, and there is no limit specified on the statements you can make or how many coins you can have.

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I agreed with the 2 correct answers and tried to find my own, what about:

"You will give me the gold coin unless this statement is false"

Either it is true and he gives you the gold coin, or it is false and he doesn't give you any coin, which makes it true. The counterargument is that it is false because he could give me any coin, but then the statement is false so that he won't give me a coin which makes the statement true. It is a bit more confusing than the other answers, but I think it should still work.

Cool ideas

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To get all the coins,

"You will either give me all the coins, or you will give me nothing."

It either creates a paradox, or it forces the hand of the dealer.

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To get all the coins,

"You will either give me all the coins, or you will give me nothing."

It either creates a paradox, or it forces the hand of the dealer.

cool

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What about "there is a gold coin and I want it." wouldn't that work?

Edited by simonshark

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What about "there is a gold coin and I want it." wouldn't that work?

Being as that is a true statement, but does not force a decision on which coin they will give you, no.

You do want the gold coin, but that dosen't mean they have to give it to you to make your statement true.

So, you'll keep on wanting the gold coin, but you'll have the copper.

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id just say "i'm lying" and while everyones confused, take the gold coi n and run