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Related: Culture Forums, Support ForumsGah. Fiendish probability question
Suppose you were to pick one of the four answers below at random (p = 0.25 for each answer). What is the probability your pick would be correct?
A. 25%
B. 50%
C. 0%
D. 25%
baldguy
(36,649 posts)Would towel also be acceptable?
The Velveteen Ocelot
(115,836 posts)But I think the answer is 0%.
drm604
(16,230 posts)The self-referential nature of the problem combined with the given answers makes the answer a moving target.
If I say %25 then since both A and D say 25% there's a 50% chance that a random choice would pick that, but that means that %50 is the correct answer and there's only a 25% chance of picking that. But if there's a 25% chance then there's a 50% chance...
I could get out of that by saying that there's no correct answer but that means a 0% chance that I would get the right answer and C says 0% so there's a 25% chance that I'll pick that...
cyberswede
(26,117 posts)drm604
(16,230 posts)That Star Trek episode is another example of a self-referential paradox.
http://en.wikipedia.org/wiki/Category:Self-referential_paradoxes
The problem posed by the OP is a paradox. You can't say that it has an answer and you can't say that it doesn't have an answer. It's a meaningless question, just like "I am lying" is meaningless. (Of course, that robot is very poorly programmed if it can't handle nonsensical statements without going into a loop and overheating. )
Response to Recursion (Original post)
LiberalElite This message was self-deleted by its author.
femmocrat
(28,394 posts)Why are A and D the same? Is this from Common Core math or sum'thin?
drm604
(16,230 posts)See my post #5.
I highly doubt that it's in common core unless it's a demonstration regarding logic and undecidability, which is probably more a college level thing.