Logic Puzzles and reasoning
- Valerion
- Alpha Wolf
- Posts: 2803
- Joined: Fri Apr 11, 2008 8:50 pm
- Gender: Male
- Sexual preference: Gay
- Species: Werewolf
- Region: Gauteng
- Location: ::1
- Contact:
Logic Puzzles and reasoning
This thread is for logic puzzles. Unlike the other Puzzles thread, I am not just looking for the first person to post the correct answer. Instead, post whatever you think is the right answer, with no explanation at all. After some time the puzzle master will post the correct answer and the reasoning behind it.
Do not look it up on the net, and if you have seen the puzzle before, you can mention it, but please don't answer it.
Puzzle 1 - Answer posted on 27 July:
Given: A set of cards where each card have a number on one side, and a letter on the opposite side
Rule: If a card has a vowel on one side, it must have an even number on the other side.
Look at this deck of four cards: [E] [P] [8] [5]
Question: Which card or cards must be turned over in order to determine whether this particular deck follows the rule?
Do not look it up on the net, and if you have seen the puzzle before, you can mention it, but please don't answer it.
Puzzle 1 - Answer posted on 27 July:
Given: A set of cards where each card have a number on one side, and a letter on the opposite side
Rule: If a card has a vowel on one side, it must have an even number on the other side.
Look at this deck of four cards: [E] [P] [8] [5]
Question: Which card or cards must be turned over in order to determine whether this particular deck follows the rule?
- Galahad
- Posts: 1973
- Joined: Tue Mar 29, 2016 6:31 pm
- Gender: Male
- Region: Gauteng
- Location: Pretoria
Re: Logic Puzzles and reasoning
The cards labelled "E" and "5" will have to be turned over. The remaining two are ambiguous.
(This is assuming the deck of cards follows a standardized pattern with what is on their sides.)
(This is assuming the deck of cards follows a standardized pattern with what is on their sides.)
Re: Logic Puzzles and reasoning
Just [E].
- Rakuen Growlithe
- Fire Puppy
- Posts: 6726
- Joined: Tue Apr 01, 2008 2:24 pm
- Gender: Male
- Sexual preference: Bi
- Species: Growlithe (pokemon)
- Region: Other
- Location: Pretoria
- Contact:
Re: Logic Puzzles and reasoning
I got asked this on IRC. Gave the right answer then panicked and changed it. Was too much pressure. x.x
"If all mankind minus one, were of one opinion, and only one person were of the contrary opinion, mankind would be no more justified in silencing that one person, than he, if he had the power, would be justified in silencing mankind."
~John Stuart Mill~
“Give me the liberty to know, to utter, and to argue freely according to conscience, above all liberties.”
~John Milton~
~John Stuart Mill~
“Give me the liberty to know, to utter, and to argue freely according to conscience, above all liberties.”
~John Milton~
- Galahad
- Posts: 1973
- Joined: Tue Mar 29, 2016 6:31 pm
- Gender: Male
- Region: Gauteng
- Location: Pretoria
Re: Logic Puzzles and reasoning
Will the answer be revealed today?
- Valerion
- Alpha Wolf
- Posts: 2803
- Joined: Fri Apr 11, 2008 8:50 pm
- Gender: Male
- Sexual preference: Gay
- Species: Werewolf
- Region: Gauteng
- Location: ::1
- Contact:
Re: Logic Puzzles and reasoning
You need to turn over 2 cards, [E] and [5]. Turning over the other 2 are wrong, because they cannot give you information. Full explanation here (I changed the card values, but the rest is the same), but in short this was some first-order logic. Interesting that 4% get it right in the abstract case, but in a practical case it rises very high. Clearly humans have issues reasoning in abstract logic.
- Galahad
- Posts: 1973
- Joined: Tue Mar 29, 2016 6:31 pm
- Gender: Male
- Region: Gauteng
- Location: Pretoria
Re: Logic Puzzles and reasoning
Magnificent!
When will the next puzzle be posted, and by whom?
When will the next puzzle be posted, and by whom?
- Valerion
- Alpha Wolf
- Posts: 2803
- Joined: Fri Apr 11, 2008 8:50 pm
- Gender: Male
- Sexual preference: Gay
- Species: Werewolf
- Region: Gauteng
- Location: ::1
- Contact:
Re: Logic Puzzles and reasoning
Whomever wants to go next.StargazingSerpent wrote:Magnificent!
When will the next puzzle be posted, and by whom?
- Galahad
- Posts: 1973
- Joined: Tue Mar 29, 2016 6:31 pm
- Gender: Male
- Region: Gauteng
- Location: Pretoria
Re: Logic Puzzles and reasoning
Given that there has not yet been a response, I shall take the liberty of doing so, please.
I created the puzzle, so there is no solution available online. The answer shall be revealed on the evening of 30 July (tomorrow).What is the missing number, indicated by '?', in this sequence?:
22344/221324, 5/15, 110002/213012, 32/1312, 667/?
Re: Logic Puzzles and reasoning
I tried, I failed. I tried hex and binary, I tried flipping, I tried factorisation. I can see there's some sort of symmetry transformation but I just can't put my finger on it.
- Galahad
- Posts: 1973
- Joined: Tue Mar 29, 2016 6:31 pm
- Gender: Male
- Region: Gauteng
- Location: Pretoria
Re: Logic Puzzles and reasoning
The rules of this thread do not mention hints, and I know you are intelligent enough as not to need them.
However, I shall say this:
Those are not fractions. Focus on simple patterns in the digits (for example - in the numbers to the right of the slashes, do you see something interesting about every second digit?), not complex mathematical ones as a whole.
A bright child may actually solve this quicker than an educated adult, simply due to the difference in approach.
However, I shall say this:
Those are not fractions. Focus on simple patterns in the digits (for example - in the numbers to the right of the slashes, do you see something interesting about every second digit?), not complex mathematical ones as a whole.
A bright child may actually solve this quicker than an educated adult, simply due to the difference in approach.
Re: Logic Puzzles and reasoning
I didn't treat them as fractions from the start, but now that you made it obvious it was no fun solving it. :'(
2617
2617
- Galahad
- Posts: 1973
- Joined: Tue Mar 29, 2016 6:31 pm
- Gender: Male
- Region: Gauteng
- Location: Pretoria
Re: Logic Puzzles and reasoning
(... My sincerest apologies. I forgot I had to reveal the answer and bring an end to my turn. o_o)
Leeward is correct. The answer is 2617.
Explanation: Each term has a "numerator" - a number on the left of the forward slash - and a "denominator" - a number on the right of the forward slash. There is no relationship between each term; instead, the only relationship that exists is between a numerator and a denominator. Each numerator is randomly generated and independent; however, the denominator "counts" the frequency of each digit in the numerator in the following way:
Let us say the numerator is 1152.
From left to right, there are two 1s, one 5, and one 2.
Hence, the numerator will 21 15 12.
211512.
Similarly, the denominator for 7772 will be three 7s, one 2: 37 12. 3712.
The pattern thus emerges that each odd digit in the denominator is the frequency (number of occurrences) the next digit, in the numerator.
Leeward is correct. The answer is 2617.
Explanation: Each term has a "numerator" - a number on the left of the forward slash - and a "denominator" - a number on the right of the forward slash. There is no relationship between each term; instead, the only relationship that exists is between a numerator and a denominator. Each numerator is randomly generated and independent; however, the denominator "counts" the frequency of each digit in the numerator in the following way:
Let us say the numerator is 1152.
From left to right, there are two 1s, one 5, and one 2.
Hence, the numerator will 21 15 12.
211512.
Similarly, the denominator for 7772 will be three 7s, one 2: 37 12. 3712.
The pattern thus emerges that each odd digit in the denominator is the frequency (number of occurrences) the next digit, in the numerator.
- Galahad
- Posts: 1973
- Joined: Tue Mar 29, 2016 6:31 pm
- Gender: Male
- Region: Gauteng
- Location: Pretoria
Re: Logic Puzzles and reasoning
It would seem no-one else is keen to begin a new puzzle. Hence, with the hope that I have been forgiven for my lack of punctuality with the previous puzzle, I shall present another one of my own making (with inspiration from a puzzle game I played):
The solution shall be revealed on Monday (30 August) evening.Observe the following grid of numbers:
Thou shalt not criticize Galahad's use of MS paint!
This is what is known as a magic square. It works as follows:
• All the digits in a column (vertical), row (horizontal), or diagonal must add up to the same amount.
• Only a single digit can occupy each of the blocks. (i.e no number greater than 9)
• Each of the digits from 1 to 9 may only be used once. You may not use a digit more than once. 0 cannot be used.
The 1 and 2 have already been inserted, leaving digits 3 to 9. Indicate where they fit in, in order to satisfy the above conditions.
- Trace
- Snep's Best Doggo
- Posts: 1155
- Joined: Fri Jul 22, 2016 9:44 pm
- Gender: Female
- Sexual preference: Bi
- Species: Wolfdog/Shapeshifter
- Region: Other
- Location: Lincoln, NE
Re: Logic Puzzles and reasoning
I think I figured out the answer. I'll PM you the solution, and if you confirm that it's right I'll post it in a couple days, with a brief explanation. I want to give everyone else a chance first though.Galahad wrote:It would seem no-one else is keen to begin a new puzzle. Hence, with the hope that I have been forgiven for my lack of punctuality with the previous puzzle, I shall present another one of my own making (with inspiration from a puzzle game I played):
The solution shall be revealed on Monday (30 August) evening.Observe the following grid of numbers:
Magic Square.png
Thou shalt not criticize Galahad's use of MS paint!
This is what is known as a magic square. It works as follows:
• All the digits in a column (vertical), row (horizontal), or diagonal must add up to the same amount.
• Only a single digit can occupy each of the blocks. (i.e no number greater than 9)
• Each of the digits from 1 to 9 may only be used once. You may not use a digit more than once. 0 cannot be used.
The 1 and 2 have already been inserted, leaving digits 3 to 9. Indicate where they fit in, in order to satisfy the above conditions.
"I change shapes just to hide in this place, but I'm still, I'm still an animal" -Miike Snow, 'Animal'
"Where there's life, there's hope."-Terence
"Where there's life, there's hope."-Terence
- Rakuen Growlithe
- Fire Puppy
- Posts: 6726
- Joined: Tue Apr 01, 2008 2:24 pm
- Gender: Male
- Sexual preference: Bi
- Species: Growlithe (pokemon)
- Region: Other
- Location: Pretoria
- Contact:
Re: Logic Puzzles and reasoning
I am so eager to see how this happens.Galahad wrote:The solution shall be revealed on Monday (30 August) evening.
"If all mankind minus one, were of one opinion, and only one person were of the contrary opinion, mankind would be no more justified in silencing that one person, than he, if he had the power, would be justified in silencing mankind."
~John Stuart Mill~
“Give me the liberty to know, to utter, and to argue freely according to conscience, above all liberties.”
~John Milton~
~John Stuart Mill~
“Give me the liberty to know, to utter, and to argue freely according to conscience, above all liberties.”
~John Milton~
- Galahad
- Posts: 1973
- Joined: Tue Mar 29, 2016 6:31 pm
- Gender: Male
- Region: Gauteng
- Location: Pretoria
Re: Logic Puzzles and reasoning
29 August. As you can see from the time signature, I posted this at approximately midnight, and simply confused the two dates.
-
- Posts: 1616
- Joined: Wed Nov 18, 2015 9:15 am
- Species: Funambulus palmarum (Squirrel)
- Region: Gauteng
Re: Logic Puzzles and reasoning
Likely cross-site scripting and SQL injection exploits.Rakuen Growlithe wrote:I am so eager to see how this happens.Galahad wrote:The solution shall be revealed on Monday (30 August) evening.
Re: Logic Puzzles and reasoning
To corrupt the calendar into showing impossible dates? Seems a bit circuitous.Randall wrote:Likely cross-site scripting and SQL injection exploits.Rakuen Growlithe wrote:I am so eager to see how this happens.Galahad wrote:The solution shall be revealed on Monday (30 August) evening.
- Galahad
- Posts: 1973
- Joined: Tue Mar 29, 2016 6:31 pm
- Gender: Male
- Region: Gauteng
- Location: Pretoria
Re: Logic Puzzles and reasoning
Some supervillains wish to take over the world. My agenda is to change calendars, it seems.
- Faanvolla
- Plaas Brak
- Posts: 1962
- Joined: Thu Jun 21, 2012 12:55 am
- Gender: Male
- Sexual preference: Gay
- Species: Dog (Vampire)
- Region: Western Cape
- Location: Stellenbosch
- Contact:
Re: Logic Puzzles and reasoning
#GregorianMustFall
Seize the day, not your bearings.
Steam, Rockstar SocialClub, Uplay, Battlenet: Faanvolla#2539, Telegram: @Faanvolla
Switch Code: SW-0054-4917-1029
DeviantArt,Furaffinity,SoFurry, Weasyl, FurryNetwork
ProfilePic by hanimetion
Steam, Rockstar SocialClub, Uplay, Battlenet: Faanvolla#2539, Telegram: @Faanvolla
Switch Code: SW-0054-4917-1029
DeviantArt,Furaffinity,SoFurry, Weasyl, FurryNetwork
ProfilePic by hanimetion
- Galahad
- Posts: 1973
- Joined: Tue Mar 29, 2016 6:31 pm
- Gender: Male
- Region: Gauteng
- Location: Pretoria
Re: Logic Puzzles and reasoning
Trace submitted a correct solution to me via PM.
The solution is...
This digit configuration satisfies all three conditions. Each row, diagonal and column adds up to 15, and no digit is used more than once.
There is a pattern in solving it. Firstly, one should fill the centre block because 4 of the 8 columns, rows and diagonals use it. Why use 5? Because that is the middle or median digit between 1 and 9.
Once you have 5, solving the remainder becomes easier. If you write out 1 to 9 and ignore 5, you can pair the leftmost digit, 1, with the rightmost digit, 9. So, 9 would go opposite to 1. You then move on the second leftmost and second rightmost: 2 and 8.
Continue this pattern, and you will have solved the square.
The solution is...
This digit configuration satisfies all three conditions. Each row, diagonal and column adds up to 15, and no digit is used more than once.
There is a pattern in solving it. Firstly, one should fill the centre block because 4 of the 8 columns, rows and diagonals use it. Why use 5? Because that is the middle or median digit between 1 and 9.
Once you have 5, solving the remainder becomes easier. If you write out 1 to 9 and ignore 5, you can pair the leftmost digit, 1, with the rightmost digit, 9. So, 9 would go opposite to 1. You then move on the second leftmost and second rightmost: 2 and 8.
Continue this pattern, and you will have solved the square.
- Trace
- Snep's Best Doggo
- Posts: 1155
- Joined: Fri Jul 22, 2016 9:44 pm
- Gender: Female
- Sexual preference: Bi
- Species: Wolfdog/Shapeshifter
- Region: Other
- Location: Lincoln, NE
Re: Logic Puzzles and reasoning
Well, you beat me to posting the solution. My thought process on solving it was a little different. Based on the fact that 1 and 2 were given, I made the assumption that being the lowest numbers, they had to share columns with the highest number, 9, placing it in the top center. From there, our methods were similar. You probably gave a better explanation for the answer than I could anyway...
"I change shapes just to hide in this place, but I'm still, I'm still an animal" -Miike Snow, 'Animal'
"Where there's life, there's hope."-Terence
"Where there's life, there's hope."-Terence
- Galahad
- Posts: 1973
- Joined: Tue Mar 29, 2016 6:31 pm
- Gender: Male
- Region: Gauteng
- Location: Pretoria
Re: Logic Puzzles and reasoning
On the contrary, Trace: Your explanation is easier to follow than mine and just as correct! Our two methods are very similar, but I appreciate your contribution. Thank you for the solution and the explanation.
I have given two puzzles in a row, now: it may be time for someone else to give us something to solve.
I have given two puzzles in a row, now: it may be time for someone else to give us something to solve.
- Rakuen Growlithe
- Fire Puppy
- Posts: 6726
- Joined: Tue Apr 01, 2008 2:24 pm
- Gender: Male
- Sexual preference: Bi
- Species: Growlithe (pokemon)
- Region: Other
- Location: Pretoria
- Contact:
Re: Logic Puzzles and reasoning
You are the mayor of a town. Half the town isn't speaking to the other half of the town. A few houses on one end of the town want to declare independence. Scattered through the town are some people that want anyone who disagrees with them to be kicked out the town. A second group wants them to be kicked out of the town and starts to riot if you disagree with them. If you kick them out then a third group promises to riot. Many people all throughout the town are upset that the other groups are fighting with each other. Others throughout the town get equally upset if you "suppress" the fighting groups. What do you do?Galahad wrote:it may be time for someone else to give us something to solve.
"If all mankind minus one, were of one opinion, and only one person were of the contrary opinion, mankind would be no more justified in silencing that one person, than he, if he had the power, would be justified in silencing mankind."
~John Stuart Mill~
“Give me the liberty to know, to utter, and to argue freely according to conscience, above all liberties.”
~John Milton~
~John Stuart Mill~
“Give me the liberty to know, to utter, and to argue freely according to conscience, above all liberties.”
~John Milton~
- Raven Song
- Stealer of Time
- Posts: 7039
- Joined: Tue Apr 24, 2012 8:56 pm
- Gender: Does it matter?
- Sexual preference: Other
- Species: Shapeshifting Anubian
- Region: Other
- Location: Londonium ONce more...
- Contact:
Re: Logic Puzzles and reasoning
Go to the pub and have a drink
Learn the rules like a pro, so you can break them like an artist. Pablo Picasso
Re: Logic Puzzles and reasoning
Feed everyone Marmite.Rakuen Growlithe wrote:What do you do?
This was a serious solution proposed to stabilize the Middle East. The theory was that a lack of zinc makes people argumentative, and the average Middle Eastern diet does not include high levels of zinc. So by carpet-bombing them with Marmite, you could remove the base chemical deficiency that's causing the conflict.
- Galahad
- Posts: 1973
- Joined: Tue Mar 29, 2016 6:31 pm
- Gender: Male
- Region: Gauteng
- Location: Pretoria
Re: Logic Puzzles and reasoning
Very subtle, Rakuen.
I am afraid I am going to have to ask for some clarification before attempting to answer, as there are some points that, at least from my view, are somewhat ambiguous:
1) Will the group wishing to declare independence accept as residents any of those who initially might not?
2) When you say that one group wants any who disagree with it to be kicked out, do you mean disagree with them as a group (i.e they hold a shared belief), or individually?
3) You mentioned that the "third group" will riot if one of the two other disagreeing groups is kicked out. Which of the other two groups is being referred to?
4) Can I assume the two halves of the town simply cannot talk to each other?
I am afraid I am going to have to ask for some clarification before attempting to answer, as there are some points that, at least from my view, are somewhat ambiguous:
1) Will the group wishing to declare independence accept as residents any of those who initially might not?
2) When you say that one group wants any who disagree with it to be kicked out, do you mean disagree with them as a group (i.e they hold a shared belief), or individually?
3) You mentioned that the "third group" will riot if one of the two other disagreeing groups is kicked out. Which of the other two groups is being referred to?
4) Can I assume the two halves of the town simply cannot talk to each other?
- Rakuen Growlithe
- Fire Puppy
- Posts: 6726
- Joined: Tue Apr 01, 2008 2:24 pm
- Gender: Male
- Sexual preference: Bi
- Species: Growlithe (pokemon)
- Region: Other
- Location: Pretoria
- Contact:
Re: Logic Puzzles and reasoning
Are countries where they eat more Marmite less argumentative than other places? I like Raven's answer though. I have to say I don't have an answer though. No matter how much gets clarified there are always new groups and new fights and new interests that are in conflict. Don't think there is a solution. I guess that means it's a bad puzzle...
"If all mankind minus one, were of one opinion, and only one person were of the contrary opinion, mankind would be no more justified in silencing that one person, than he, if he had the power, would be justified in silencing mankind."
~John Stuart Mill~
“Give me the liberty to know, to utter, and to argue freely according to conscience, above all liberties.”
~John Milton~
~John Stuart Mill~
“Give me the liberty to know, to utter, and to argue freely according to conscience, above all liberties.”
~John Milton~
Re: Logic Puzzles and reasoning
Marmite specifically? Maybe not, but let me show you two maps. The first, a map showing countries hostile to the Christian faith, graded by risk of physical persecution. So take this one as a Religious Diversity Intolerance Index:Rakuen Growlithe wrote:Are countries where they eat more Marmite less argumentative than other places?
The second map, percentage of population that is Muslim - otherwise known as a Inverse Likelihood of Bacon Consumption map:
One possible conclusion is systemic religious intolerance. The other conclusion is that bacon makes you peaceful, and a survey of 1/1 bacon eaters (myself) validates this hypothesis.