• Reddfugee42@lemmy.world
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    19 days ago

    This is a self-referential paradox — a classic logic puzzle designed to be tricky. Let’s break it down:

    Step-by-step analysis:

    1. How many choices? There are 4 possible answers, so if we pick one randomly, the chance of picking any specific one is 1 in 4 = 25%.

    2. How many answers say “25%”? Two.

    3. That means the probability of randomly choosing an answer that says “25%” is 2 in 4 = 50%.

    4. But if the correct answer is 50%, then only one option says “50%” — which is ©. So the probability of picking it at random is 1 in 4 = 25%, contradicting the idea that 50% is correct.

    5. If the correct answer is 25%, then two options say that — a and d. So the chance of picking one of those at random is 50%, not 25% — again a contradiction.

    6. Similarly, if 60% is correct (only one option), then the chance of picking it randomly is 25%, which again makes it incorrect.

    Conclusion: Any choice leads to a contradiction. This is a self-referential paradox, meaning the question breaks logical consistency. There is no consistent correct answer.

    • zkfcfbzr@lemmy.world
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      19 days ago

      It is 33% if the answer itself is randomly chosen from 25%, 50%, and 60%. Then you have:

      If the answer is 25%: A 1/2 chance of guessing right

      If the answer is 50%: A 1/4 chance of guessing right

      If the answer is 60%: A 1/4 chance of guessing right

      And 1/3*1/2 + 1/3*1/4 + 1/3*1/4 = 1/3, or 33.333…% chance

      If the answer is randomly chosen from A, B, C, and D (With A or D being picked meaning D or A are also good, so 25% has a 50% chance of being the answer) then your probability of being right changes to 37.5%.

      This would hold up if the question were less purposely obtuse, like asking “What would be the probability of answering the following question correctly if guessing from A, B, C and D randomly, if its answer were also chosen from A, B, C and D at random?”, with the choices being something like “A: A or D, B: B, C: C, D: A or D”

  • TheFogan@programming.dev
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    19 days ago

    Selecting not at random, A xor D must be correct, because the answer key can only have one correct answer so even duplicate right answers must also be wrong.

    • waigl@lemmy.world
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      19 days ago

      It asked for whether the answer is correct not whether it lines up with the answer sheet.

  • sqgl@beehaw.org
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    18 days ago

    It was only the next day that I returned to this post realising that “this question” isn’t even defined.

  • Lucien [he/him]@mander.xyz
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    19 days ago

    This is a paradox, and I don’t think there is a correct answer, at least not as a letter choice. The correct answer is to explain the paradox.

    • Feydaikin@beehaw.org
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      19 days ago

      You can rationalize your way to exclude all but a last answer, there by making it the right answer.

      Like, seeing as there are two 25% options, so there aren’t four different answers, which means there isn’t a 25% chance. This lead to there only being two options left 50% or 60%. This would seem to make 50% the right answer, but it’s not, because you know the options, so it’s not random, which in turn means you’re not guessing. So you have more that 50% chance of choosing the right answer. So 60% is the closest to a right answer, by bullshitting and gaslighting yourself into thinking you solved question.

      • Didros@beehaw.org
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        18 days ago

        Having been to school I know a teacher did not read this question so tge answer is probably A, B, C, or D. Chosen randomly of course. But you will get credit for 3/4 answers as long as you take the time to talk to the teacher during office hours.

  • Nounka@lemmy.world
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    18 days ago

    I would think a b c d so 25% O he made a mistake znd forgot to take the bubble answer out. Now we only can pick between aord b c so it would be 33%

    Seems my logic is wrong iff i read the rest