Brain Teasers Q&A Game - Answer the First Question Now!

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Discussion Overview

The discussion revolves around a brain teaser game where participants answer riddles and set new questions based on correct answers. The initial brain teaser involves a bear's color based on its movement, followed by various riddles and their interpretations, including a riddle about the inhabitants of Funkytown and a factorial-related question.

Discussion Character

  • Exploratory
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • Participants agree that the bear must be at the North Pole to return to the starting point, leading to the conclusion that it is a polar bear, thus white.
  • One participant questions whether the bear could be a brown or black bear transferred to the Arctic, introducing a speculative scenario.
  • A new riddle about inhabitants in Funkytown prompts discussion on the maximum number of inhabitants, with one participant suggesting it could be 483,207 based on the conditions provided.
  • Another participant argues that the answer could be 0, proposing a scenario where the conditions lead to an infinite regression of inhabitants with varying hair counts.
  • There is a discussion about the inclusion of bald inhabitants, with some participants noting that this could affect the interpretation of the riddle.
  • A factorial-related question is posed, leading to calculations and discussions about remainders when dividing sums of factorials by 7, with some participants making errors in their reasoning.
  • Participants explore a letter sequence riddle, with discussions on the logic behind the sequence and the significance of the letters representing the last letters of numbers.

Areas of Agreement / Disagreement

Participants generally agree on the interpretation of the initial bear riddle, but there are competing views regarding the Funkytown riddle and the factorial question. The discussions remain unresolved with differing interpretations and calculations presented.

Contextual Notes

Some participants express uncertainty about the conditions of the Funkytown riddle and the implications of including bald inhabitants. Additionally, there are unresolved mathematical steps in the factorial discussion, with participants correcting themselves and others.

Who May Find This Useful

Individuals interested in brain teasers, riddles, and mathematical reasoning may find this discussion engaging and thought-provoking.

Hootenanny
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The aim of the game is simple (similar to the Math Q&A game). I will post a brain teaser, the first person to give the correct answer gets to set the next question, the first person to then answer this question correctly gets to set the following question... ad infinitum. A few rules before we begin;

  1. The person who sets the brain teaser has the final and only decision as to who answered the question correctly.
  2. No new question may be posted until the person who set the current question has indicated who has answered the question correctly first.
  3. The person who was identified as answering the brain teaser correctly, by the person who set the current question, may then post one of their own brain teasers.
  4. Each answer must be accompanied by an explanation. Any answer, correct or otherwise, which is not qualified with an explanation shall be disqualified.
  5. The person whom set the question may at his/her discretion post the solution to the brain teaser which he/she has set and nominate another person to set the next question.

Let the games begin ... :biggrin:

First Question

A bear walks south for one kilometer, then it walks west for one kilometer, then it walks north for one kilometer and ends up at the same point from which it started. What color was the bear?
 
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He must have been standing at the north pole in order to arrive at the same point. Thus he was white because he was a polar bear? lol.
 
dontdisturbmycircles said:
He must have been standing at the north pole in order to arrive at the same point. Thus he was white because he was a polar bear? lol.
Correct! Your turn...
 
>>White - It's a polar bear, and it probably started walking from the north pole. [/color]<<

I don't have any interesting brain teasers right now . Can I let someone else post a question? (in the case that I've posted the correct answer before anyone else does)

(Just can't resist answering questions, you know :biggrin:)
 
Great! I have the right answer and I don't have to post a questions! :biggrin:

Edit: Why can't it be a brown bear, or black bear that was transferred to the Arctic for some experiment?
 
I am going to need to be solving this as you are... I was caught unprepared lol, but I found one that looks sort of interesting, so here goes.

In the city of Funkytown, the following facts are true:

No two inhabitants have exactly the same number of hairs.
No inhabitant has exactly 483,207 hairs.
There are more inhabitants than there are hairs on the head of anyone inhabitant.
What is the largest possible number of inhabitants of Funkytown?
 
I think this riddle is a dud, I don't see a limit? lol am I just tired?
 
I think I have it. The riddle states that there is no one with 483,207 hairs, therefore we can say that there may be 483,207 inhabitants with between [0, 483 206] hairs on their head. However, if there were more than 483,207 inhabitants this would violate the third condition. Therefore, the maximum number of inhabitants is 483,207.

What say you?
 
I see the answer as being 0. In the minimum case there is 1 man with 1 hair, that causes there to also be another man with more than one hair, which causes there to be another man with more than 2 hairs, add infinitum. So 0 is the only plausible answer.

edit: hold on let me read your post, didn't see it.
 
  • #10
dontdisturbmycircles said:
I see the answer as being 0. In the minimum case there is 1 man with 1 hair, that causes there to also be another man with more than one hair, which causes there to be another man with more than 2 hairs, add infinitum. So 0 is the only plausible answer.

That was nice.

edit: How about this case, one man with one hair, and another, who is bald. Conditions satisfied, no?

edit2: Is it specified that there are no bald inhabitants?
 
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  • #11
edit:double post
 
  • #12
Makes sense to me, your turn. Thank god, I can go to sleep now. Good night! :-)

I didn't even think of including a bald guy. lol

If every man had at least 1 hair, then 0 would be right. :P
 
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  • #13
dontdisturbmycircles said:
I didn't even think of including a bald guy. lol
I very nearly didn't; I was about to submit my answer when I re-read the conditions.

Anyway the next teaser;

Find the remainder if we divide {\color{blue}1!+2!+3!+\ldots +100!} by 7
 
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  • #14
Thankfully, there is a weekly that we subscribe to which has this little teaser in every issue. Most of them are simple enough.

Fill in the blank so that line 4 is consistent with the first three.

Triangle, Pentagon, Square

Square, Hexagon, Hexagon, Square

Pentagon, Hexagon, Hexagon, Hexagon, Square, Triangle

Hexagon, Octagon, Octagon, Octagon, Octagon, __________
 
  • #15
neutrino said:
edit: How about this case, one man with one hair, and another, who is bald. Conditions satisfied, no?
Except we are to find the maximum number of inhabitants.
 
  • #16
Oops! Didn't notice Hoot's post. I though 'circles was referring to me.

Anyway, I'm not planning to delete the stuff I typed. :-p You can solve this, too, "outside" the game. :smile:
 
  • #17
Hootenanny said:
Find the remainder if we divide {\color{blue}1!+2!+3!+\ldots +100!} by 7

Since all the terms from 7! to 100! are evenly dividisble by 7, we only need to find the remainder of (1!+2!+3!+4!+5!+6!)/7, which is 5 :)

DaveE
 
  • #18
edit:woops I did this wrong, lol. I really need to go to bed. goodnight
 
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  • #19
davee123 said:
Since all the terms from 7! to 100! are evenly dividisble by 7, we only need to find the remainder of (1!+2!+3!+4!+5!+6!)/7, which is 5 :)

DaveE
Correct! Your turn davee...
dontdisturbmycircles said:
I am just now learning about factorial stuff, but I think I can answer this. Noting that all numbers above 7! are divisible by 7, we have 1! 2!... 6! to deal with

\frac{1!+2!+3!...6!}{7}=124.7

edit:woops derr I did this wrong, I was supposed to take the remainder of each term. lol. I really need to go to bed. goodnight
Yeah, you nearly had it...till davee stole your thunder!
 
  • #20
Hootenanny said:
Correct! Your turn davee...

Alright... What letter comes next?

o, e, o, e, r, e, x, ?

DaveE
 
  • #21
davee123 said:
Alright... What letter comes next?

o, e, o, e, r, e, x, ?

DaveE

Well, the last six letters are the last letters of numbers in a row eg. x is the last letter of six, e is the last letter of five, r is the last letter of four and e is the last letter of three, o is the last letter of two, e is the last letter of e. However, I'm not sure what the first o stands for.

If I continue this series, then I would get an n since that is the last letter in the number seven?

Edit: o is the last letter in zero
 
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  • #22
Moridin said:
Well, the last six letters are the last letters of numbers in a row eg. x is the last letter of six, e is the last letter of five, r is the last letter of four and e is the last letter of three, o is the last letter of two, e is the last letter of e. However, I'm not sure what the first o stands for.

If I continue this series, then I would get an n since that is the last letter in the number seven?

Edit: o is the last letter in zero

Exactly! I hoped the "zero" might throw people off. I was actually tempted to start the sequence at "negative three", yielding:

e, o, e, o, e, o, e, r, e, x

But I figured that might be a bit too confusing and arbitrary.

DaveE
 
  • #23
neutrino said:
Thankfully, there is a weekly that we subscribe to which has this little teaser in every issue. Most of them are simple enough.

Fill in the blank so that line 4 is consistent with the first three.

Triangle, Pentagon, Square

Square, Hexagon, Hexagon, Square

Pentagon, Hexagon, Hexagon, Hexagon, Square, Triangle

Hexagon, Octagon, Octagon, Octagon, Octagon, __________

This one was a pain in the a-- :-). When I first saw it I thought that it would have to do with Pascal's triangle, but within 30 seconds it became apparent that it didn't. Eventually I noticed the first shape always has one more side than in the sentence before it. So perhaps it is just a number used to make a list. Then I noticed that 3 was dividible by 9, and then it was easy to tie it all together.

Square.

3^2 [5+4]

4^2 [6+6+4]

5^2 [6+6+6+4+3]

6^2 [8+8+8+8+4]
 
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  • #24
I have a feeling that Moridin won't be back.
 
  • #25
dontdisturbmycircles said:
Square.

3^2 [5+4]

4^2 [6+6+4]

5^2 [6+6+6+4+3]

6^2 [8+8+8+8+4]

That's a correct answer. It could also be any other quadrilateral.
 
  • #26
Hootenanny said:
A bear walks south for one kilometer, then it walks west for one kilometer, then it walks north for one kilometer and ends up at the same point from which it started. What color was the bear?
I thought this might be Bernhard (from German for "brave bear") Jensen, the captain of the "Southern Cross" Antarctic Expedition. I also thought that after a 3 mile walk in the cold, the captain would be all blue! :biggrin:
 
  • #27
Gokul43201 said:
I thought this might be Bernhard (from German for "brave bear") Jensen, the captain of the "Southern Cross" Antarctic Expedition. I also thought that after a 3 mile walk in the cold, the captain would be all blue! :biggrin:
:smile: Your capacity for remembering inane trivia amazes me...:-p
 
  • #28
dontdisturbmycircles said:
I have a feeling that Moridin won't be back.

I live for contests. You shouldn't be trusting your instinct :-p

I've spend the last day trying to come up with a suitable and interesting brainteaser.

"On a deserted island, an evil emperor lives alone. He hates people who come to the islands and kills them. He always thinks of new and exotic ways of doing so and there are no two alike, although he has a strange sense of humor - he gives them one chance of survival.

He allows them to guess once on the execution style he has in mind for them. If the person guess correctly, they will be hung. If they guess incorrectly, they will be shot."

If you get caught by the emperor and you wish to survive, what style of execution shall you guess on?
 
  • #29
Moridin said:
"On a deserted island, an evil emperor lives alone. He hates people who come to the islands and kills them. He always thinks of new and exotic ways of doing so and there are no two alike, although he has a strange sense of humor - he gives them one chance of survival.

He allows them to guess once on the execution style he has in mind for them. If the person guess correctly, they will be hung. If they guess incorrectly, they will be shot."

If you get caught by the emperor and you wish to survive, what style of execution shall you guess on?
You should choose to be shot. This would create a paradox, since the statement is true implying you should be hung, however, if you are hung the statement is false implying you should be shot. The emperor can do nothing but let you go.
 
  • #30
Hootenanny said:
You should choose to be shot. This would create a paradox, since the statement is true implying you should be hung, however, if you are hung the statement is false implying you should be shot. The emperor can do nothing but let you go.

And I can do nothing but say that you are correct.
 

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