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Quiz Master’s Master Quiz

Just a little quiz in which the questions are (I hope) incredibly challenging. :smile:

Question 1:

Alice and Bob have displeased the great Emperor Charlie in some way. As a punishment, both Alice and Bob are locked up in separate dungeons with no way to communicate with each other.

Every day a guard will come in to their dungeon and flip a coin. Alice and Bob must then guess what the result of the other person’s coin flip was. If either of them guess correctly, they will live for another day.

Before being sent to the dungeons, Alice and Bob managed to create a strategy in which they would be able to live indefinitely. What was the strategy?

QM

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Original post by Quiz Master
Just a little quiz in which the questions are (I hope) incredibly challenging. :smile:

Question 1:

Alice and Bob have displeased the great Emperor Charlie in some way. As a punishment, both Alice and Bob are locked up in separate dungeons with no way to communicate with each other.

Every day a guard will come in to their dungeon and flip a coin. Alice and Bob must then guess what the result of the other person’s coin flip was. If either of them guess correctly, they will live for another day.

Before being sent to the dungeons, Alice and Bob managed to create a strategy in which they would be able to live indefinitely. What was the strategy?

QM


Ahh... that's a teaser. Probably not right, but do they have double sided coins that they alternate between in some pattern?
Original post by Kevin De Bruyne
Ahh... that's a teaser. Probably not right, but do they have double sided coins that they alternate between in some pattern?


Nope. These are fair coins that have a heads and a tails :smile:

QM
Reply 3
Avatar for Kindred
Kindred
20
Deceptively simple. Only two possibilities for the flip, two people and only one has to get it right each time. One always guesses heads and one always guesses tails.One of them will always get it right and one will always get it wrong.

That or one of them calls in a favour with some god-like being for immortality. Seems more likely tbh since they're living "indefinitely" not just until they die naturally :wink:
(edited 6 years ago)
To hire a better lawyer (dunno)
Original post by Kindred
Deceptively simple. Only two possibilities for the flip, two people and only one has to get it right each time. One always guesses heads and one always guesses tails.One of them will always get it right and one will always get it wrong.


They can't communicate so can't coordinate who says heads and who says tails. Plus they guess the other persons flip so 2 flips. If person a guesses heads when it was tails and person b calls tails when it was heads they would fail.
(edited 6 years ago)
Reply 6
Avatar for Kindred
Kindred
20
Original post by Guru Jason
They can't communicate so can't coordinate who says heads and who says tails.


Wouldn't works anyway. There are two coin flips.
I didn't read the question properly.

I assume they can hear each other's guess so the first "guesses" what their own was and the other "guesses" the same.
Original post by Kindred
Wouldn't works anyway. There are two coin flips.
I didn't read the question properly.

I assume they can hear each other's guess so the first "guesses" what their own was and the other "guesses" the same.


That's what I was thinking but it says they can't due to being in separate dungeon. I'm intrigued by this puzzle though lol.
Reply 8
Avatar for Kindred
Kindred
20
Original post by Guru Jason
That's what I was thinking but it says they can't due to being in separate dungeon. I'm intrigued by this puzzle though lol.


In which case I'm sticking with making a deal with the devil. I see no other way.
It's a good puzzle. :smile:
Original post by Kindred
In which case I'm sticking with making a deal with the devil. I see no other way.
It's a good puzzle. :smile:


I looked up the full riddle and yes, each person is told the result of the other guess and they concocted the strategy before they split up. (Op missed a few bit out) so your theory holds I think.
:wtf:
Original post by Guru Jason
I looked up the full riddle and yes, each person is told the result of the other guess and they concocted the strategy before they split up. (Op missed a few bit out) so your theory holds I think.


Yay! I'm smart at a very specific thing! :biggrin:
Original post by Kindred
Yay! I'm smart at a very specific thing! :biggrin:


Yeah it didn't give an answer just a more extended version of the question just in case people think I'm cheating lol.
Original post by 04MR17
:wtf:


I wonder if you can sue QM for stealing your quiz idea :tongue:
Original post by Kindred
I wonder if you can sue QM for stealing your quiz idea :tongue:
No different format this is fine. :h: I have had people copying (exactly) my ideas in the past though. Quick thread closures sort that.:cool:
Original post by 04MR17
No different format this is fine. :h: I have had people copying (exactly) my ideas in the past though. Quick thread closures sort that.:cool:


You're such a trend starter. :biggrin:
QMs doing it justice too. Good puzzle if you ask me. I'm looking forward to a new era of awesome quizzes!
Original post by Guru Jason
I looked up the full riddle and yes, each person is told the result of the other guess and they concocted the strategy before they split up. (Op missed a few bit out) so your theory holds I think.


The other person is not told what the other person guessed :smile:

QM
(edited 6 years ago)
If you want I can give you the answer :smile:

I did not manage to work it out when I first read this problem :smile:

QM
I think I will give everyone 24 hours per question, so 11 hours left :smile:

QM
The strategy was one of them would say the result of their coin toss (so if the toss was heads, they would predict the other coin toss was the same), while the other person would predict that the coin toss was different.

This way they are guaranteed to survive an extra day

QM

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