## Introductory Riddlage

A forum for good logic/math puzzles.

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Matthias
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### Introductory Riddlage

Well, I thought I'd try posting a few. No guarantees that they're new to anyone, but I hope you enjoy them. Also, please note D and E are of my own design, although D is rather formulaic and E blissfully simple.

A) Their are five mistaiks in this sentance. Try to find them all.

B) Provided that it has no top (and therefore no means of containing helium, you clever ducks), what can you put in a barrel to make it lighter?

C) You are tied to a chair with no means of escape. I have six-shot revolver with two rounds loaded in adjacent chambers. I point the gun at your head and pull the trigger; nothing happens. I will only pull the trigger only once more--would you like me to pull it immediately, or spin the cylinder first?

D) I ride bulls before I am born. I stop blades and arrows by the power of my will. I forge weapons with my breath and protect the virtue of innocent women. I am an opener of doors and a sealer of bargains. What am I?

E) {Warning: Trick question} Two men, one with red hair and one with black, are traveling across country. They arrive at a small settlement at nightfall, and make their way to a local tavern. One of them asks the tavernkeeper for a room. Was it the black-haired man or the red-haired man that asked the question?

F) This one is pretty much presented for amusement, as it's quite silly and I'm rather certain you won't be able to weed out the intended solution unless you already know what it is. That being said, the solution is provided below.

You are in a room with no doors, no windows, and no apparent means of escape. The only thing the room contains is a small desk with a mirror on it. How do you get out?

Bob the answer genie wrote:You look in the mirror and see what you saw. You use the saw to cut the desk in half. Two halves make a (w)hole, and you walk through the hole to leave the room. See? Told you it was silly.
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prysorra
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### Re: Introductory Riddlage

Matthias wrote:A) Their are five mistaiks in this sentance. Try to find them all.

"There are four mistakes in this sentence." I'm guessing getting the wrong number counts
Matthias wrote:B) Provided that it has no top (and therefore no means of containing helium, you clever ducks), what can you put in a barrel to make it lighter?

a hole
Matthias wrote:C) You are tied to a chair with no means of escape. I have six-shot revolver with two rounds loaded in adjacent chambers. I point the gun at your head and pull the trigger; nothing happens. I will only pull the trigger only once more--would you like me to pull it immediately, or spin the cylinder first?

simple probability. Shoot again, it's 2 out 5. Spin, it's 1 out of 3.
Matthias wrote:E) {Warning: Trick question} Two men, one with red hair and one with black, are traveling across country. They arrive at a small settlement at nightfall, and make their way to a local tavern. One of them asks the tavernkeeper for a room. Was it the black-haired man or the red-haired man that asked the question?

"A tavern is, loosely, a place of business where people gather to drink alcoholic beverages and, more than likely, also be served food, though NOT LICENCED TO PUT UP GUESTS".

In other words....probably the blond.

jestingrabbit
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### Re: Introductory Riddlage

prysorra wrote:
Matthias wrote:C) You are tied to a chair with no means of escape. I have six-shot revolver with two rounds loaded in adjacent chambers. I point the gun at your head and pull the trigger; nothing happens. I will only pull the trigger only once more--would you like me to pull it immediately, or spin the cylinder first?

simple probability. Shoot again, it's 2 out 5. Spin, it's 1 out of 3.

I don't think that's right.

If we label the chambers 1, 2, 3, 4, 5 and 6, then we may as well assume that chambers 5 and 6 have the rounds in them. I'll also assume that the gun never misfires (or alternatively I'll treat the chance of that as negligible).

We know that the chamber that just fired wasn't 5 or 6, so it had to be 1, 2, 3 or 4. If it was 1, 2 or 3, we're safe, and if its 4 we're doomed, giving us a chance of 1/4 of being doomed if we don't respin, compared to 1/3 if we do.

So, don't respin the barrel.

And please, we have a spoiler policy. Its stickied at the top of the forum. Read it.

__Kit
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cephalopod9
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I wrote:
Matthias wrote:D) I ride bulls before I am born. I stop blades and arrows by the power of my will. I forge weapons with my breath and protect the virtue of innocent women. I am an opener of doors and a sealer of bargains. What am I?
Is it leather? Hide from cattle can be used to make sheilds, bellows, clothes, ???, and book bindings.

Matthias
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prysorra: good job on A and B. However, C is wrong. And as far as E goes:

Strictly speaking, I believe you're thinking of a pub. And no, that's not the answer.

jestingrabbit: correct. Incidentally, was the spoiler remark directed at me or sorra? All I read in the sticky (which I read before I posted), was the 'two-threads' rule, but most people seem to ignore this rule when the riddles given are as simple as these.

__Kit: Relevance={empty set}

<edit>
cephalopod9:
Good job. I was actually thinking of chastity belts for the protector of innocence thing, and gloves worn when shaking hands for the sealer of bargains bit, but close enough. As for the ???, well, if you really want to know... leather was once a material used for hinges, before the industrial revolution when worked metal became cheap and common enough to be used by the 'unwashed masses'
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jestingrabbit
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Matthias wrote:prysorra: good job on A and B. However, C is wrong. And as far as E goes:

Strictly speaking, I believe you're thinking of a pub. And no, that's not the answer.

jestingrabbit: correct. Incidentally, was the spoiler remark directed at me or sorra? All I read in the sticky (which I read before I posted), was the 'two-threads' rule, but most people seem to ignore this rule when the riddles given are as simple as these.

__Kit: Relevance={empty set}

<edit>
cephalopod9:
Good job. I was actually thinking of chastity belts for the protector of innocence thing, and gloves worn when shaking hands for the sealer of bargains bit, but close enough. As for the ???, well, if you really want to know... leather was once a material used for hinges, before the industrial revolution when worked metal became cheap and common enough to be used by the 'unwashed masses'

It was aimed at prysorra, they had posted solutions in clear text. Thats not cool. Either put it in a quote box as white text, cause then its white on white, or post it in a new thread. When the questions are simpleish, its okay not to use a new thread. When the question is more involved it makes sense to have a thread for discussion and clarification of the question and one for solutions with discussion of the solutions.

Mouffles
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E: The red-haired man... both the travellers have red hair, and one has black clothes or something else? The question still makes sense if we assume the tavernkeeper has black hair.
In the spirit of taking things too far - the 5x5x5x5x5 Rubik's Cube.

Token
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### Re: Introductory Riddlage

jestingrabbit wrote:I don't think that's right.

If we label the chambers 1, 2, 3, 4, 5 and 6, then we may as well assume that chambers 5 and 6 have the rounds in them. I'll also assume that the gun never misfires (or alternatively I'll treat the chance of that as negligible).

We know that the chamber that just fired wasn't 5 or 6, so it had to be 1, 2, 3 or 4. If it was 1, 2 or 3, we're safe, and if its 4 we're doomed, giving us a chance of 1/4 of being doomed if we don't respin, compared to 1/3 if we do.

So, don't respin the barrel.

Isn't it 1/2 if you do spin? We know it was 1,2,3 or 4, and 3 and 4 are the dangerous ones.

Pesto
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### Re: Introductory Riddlage

Token wrote:
jestingrabbit wrote:I don't think that's right.

If we label the chambers 1, 2, 3, 4, 5 and 6, then we may as well assume that chambers 5 and 6 have the rounds in them. I'll also assume that the gun never misfires (or alternatively I'll treat the chance of that as negligible).

We know that the chamber that just fired wasn't 5 or 6, so it had to be 1, 2, 3 or 4. If it was 1, 2 or 3, we're safe, and if its 4 we're doomed, giving us a chance of 1/4 of being doomed if we don't respin, compared to 1/3 if we do.

So, don't respin the barrel.

Isn't it 1/2 if you do spin? We know it was 1,2,3 or 4, and 3 and 4 are the dangerous ones.

It's 1/3. Two adjacent chambers out of six have a bullet. If you spin you have an equal chance of getting any one of the six chambers. 2/6 => 1/3.

Token
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### Re: Introductory Riddlage

Pesto wrote:
Token wrote:
jestingrabbit wrote:I don't think that's right.

If we label the chambers 1, 2, 3, 4, 5 and 6, then we may as well assume that chambers 5 and 6 have the rounds in them. I'll also assume that the gun never misfires (or alternatively I'll treat the chance of that as negligible).

We know that the chamber that just fired wasn't 5 or 6, so it had to be 1, 2, 3 or 4. If it was 1, 2 or 3, we're safe, and if its 4 we're doomed, giving us a chance of 1/4 of being doomed if we don't respin, compared to 1/3 if we do.

So, don't respin the barrel.

Isn't it 1/2 if you do spin? We know it was 1,2,3 or 4, and 3 and 4 are the dangerous ones.

It's 1/3. Two adjacent chambers out of six have a bullet. If you spin you have an equal chance of getting any one of the six chambers. 2/6 => 1/3.

Ah, I was thinking of something else for spinning. Never mind.

gmalivuk
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Something interesting about the gun one,

If the bullets start out in opposite chambers (which is how I originally read the question, incidentally), it becomes sort of like an inverted Monty Hall problem. If you don't spin, there's a 1/2 chance of biting the bullet, so to speak. If you do, it's only 1/3, so now you're better off spinning.

To finish out the scenario with the last possibility, suppose the bullets are separated by one empty chamber (and three on the other side). Bullets are in 1 and 3, for example. The first empty was thus 2, 4, 5, or 6. If it was 2 or 6, and you don't spin, you're fucked. 4 or 5 and you're fine. So, 1/2 probability of perishing if you don't spin, and, again, 1/3 if you do.

So, say you don't know which chambers the bullets are in, only that the choice was random. Are you better off spinning this time?
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Token
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gmalivuk wrote:Something interesting about the gun one,

If the bullets start out in opposite chambers (which is how I originally read the question, incidentally), it becomes sort of like an inverted Monty Hall problem. If you don't spin, there's a 1/2 chance of biting the bullet, so to speak. If you do, it's only 1/3, so now you're better off spinning.

To finish out the scenario with the last possibility, suppose the bullets are separated by one empty chamber (and three on the other side). Bullets are in 1 and 3, for example. The first empty was thus 2, 4, 5, or 6. If it was 2 or 6, and you don't spin, you're fucked. 4 or 5 and you're fine. So, 1/2 probability of perishing if you don't spin, and, again, 1/3 if you do.

So, say you don't know which chambers the bullets are in, only that the choice was random. Are you better off spinning this time?

Yes, because you've eliminated one hole already. It's 1/3 if you don't spin, 2/5 if you don't.

ptveite
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I'm pretty sure that the answer to E is "yes," as in, yes it was the red-haired dude or black-haired dude.

Also, Malivuk, if you dont know where they are it's simple, if you dont spin you have a 2/5 chance of dying, if you do, it's just 1/3, so you spin.

Edit: Drat! Token beat me to answering Malivuk's question.

trihedron
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You don't actually know which two chambers are full, only that the two full ones are consecutive. Label the chambers 1, 2, 3, 4, 5, 6. (1,2), (2,3), (3,4), (4,5), (5,6), (6,1) are all of the possible sequences of two shots without respinning. Because two consecutive chambers are full, there is one sequence that looks like (empty, death), one that looks like (death, death), and one that looks like (death, empty), and the rest are (empty, empty). That gives, of the six two-shot sequences, four that begin with empty. Of those four, one has the second place as "death"; in other words, having failed to kill you, you know that the barrel is at one of the four empty chambers, and that exactly one of the four empty chambers has a bullet in the next chamber. So, it's 1 chance on 4 of dying if he doesn't spin again, 1 chance in 3 of dying if he does.
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Matthias
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ptveite wins riddle E (although you should have labeled your quote to prevent spoilers for people thinking you were discussing other riddles. And that means all of them have been answered except for F, which of course has the solution included up top anyway. Jolly good show everyone, and nice discourse on the revolver problem as well.
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Defenestrator
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### Re: Introductory Riddlage

Matthias wrote:You are in a room with no doors, no windows, and no apparent means of escape. The only thing the room contains is a small desk with a mirror on it. How do you get out?
I listen to bad puns until they make me groan. My grown body then breaks the walls apart.

ptveite
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For more on riddles like E, see http://xkcd.com/169/

agreed

chenjesu
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A) Their are five mistaiks in this sentance. Try to find them all.

Actually, there are six mistakes in that sentence. "Their" should be "There," "mistaiks" should be "mistakes," "sentance" should be "sentence," "five" should be "six," "six" should be "not six," and "not six" should be "six" again.

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Matthias
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ptveite wrote:For more on riddles like E, see http://xkcd.com/169/

agreed

Hence "Warning: Trick Question." All's fair in love, war and semantics.
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jestingrabbit
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For sure, the warning was a good idea. I suppose we don't mind them around here so long as they're appropriately labeled, though personally I think they suck *eats his sour grapes*.

antonfire
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### Re: Introductory Riddlage

Matthias wrote:E) {Warning: Trick question} Two men, one with red hair and one with black, are traveling across country. They arrive at a small settlement at nightfall, and make their way to a local tavern. One of them asks the tavernkeeper for a room. Was it the black-haired man or the red-haired man that asked the question?

Yes.
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aarongoss
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### With respect to D:

Leather has never been particularly good at stopping blades or arrows, and more importantly leather has no will.

Matthias
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To Aarongoss wrote:Boiled leather armor was quite popular back in the day. It wasn't the best stuff in the world, but it was better than nothing, especially in layers. Besides which, it was used as strapping or under-layers in tougher armors such as chainmaille and field plate. And if you want to nitpick, leather shouldn't be able to soliloquize either.

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Blur
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### Re: Introductory Riddlage

My girlfriends first answer to B was
Spoiler:
a fire, because it "lights up" or illuminates the barrel, making it lighter.

dbsmith
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### Re: Introductory Riddlage

C:
Spoiler:
(Just to be pedantic) With 2 adjacent bullets, shouldn't the weight factor of the bullets be taken into account when spinning? Also, since you are trapped in the chair with no means of escape, wouldn't it be more desirable to SHOOT yourself? As opposed to starving to death

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### Re: Introductory Riddlage

When I first saw B), I thought:
Spoiler:
termites!

Willim33
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### Re: Introductory Riddlage

A I don't think has been solved.
Spoiler:
There are 5 mistakes: the 3 spelling errors are their, mistaiks and sentance (which, as has been said, should be there, mistakes and sentence). The 2 grammatical errors are that there should not be a full stop in the middle, perhaps a comma or a colon, which means there should not be a capital letter on the word try. If that's not it then maybe five should be 5, and the 5th mistake probably being very ambiguous.

B:
Spoiler:
I thought termites too, though that fire idea would work by burning it (depending on the material) as well as making it 'lighter', so it works on two levels.

C:
Spoiler:
Doesn't it depend on the gun? Would move to the next chamber automatically or not? Do you want to die or not? (On first read I thought the aim was to die).

D's been done. I had no idea.

E:
Spoiler:
People have said that the answer is neither, as a tavern would not be able to provide a room for them. It is a trick question so that is probably the correct response, though the fact the tavern should not be able to provide a room should not necessarily influence whether the ask the question in the first place. The question, then, is really unanswerable and invites some sort of prejudice over hair colour or perhaps the answer is they both do, as they both need a room, they are not together as one party in anyway so would mean they would both ask separately for separate rooms. The other possibility might be that the answer begins with 'It depends on...', either way, it doesn't quite work.

F I'd heard before and it's a little silly...
Spoiler:
Maybe the trapped person should wait for someone to rescue them, instead of going nuts trying to use homophones to escape.

Please use spoilers not white text. Where you see white text being used as a spoiler the answer predates the existence of the spoiler tags. -jr