Results are out! Find what you need...fast. Get quick advice or join the chat
Hey there! Sign in to join this conversationNew here? Join for free

Riddle/paradox question

Announcements Posted on
Will you get the grades you need for uni? Get prepared today and de-stress, sign up to email alerts for course places! 02-06-2015
Waiting on IB results? Our IB results hub explains everything you need to know 01-06-2015
  1. Offline

    ReputationRep:
    If you choose an answer to this question at random, what is the chance you will be correct.

    a. 25%

    b.50%

    c.60%

    d.25%

    Read it and its been bugging me ever since. Which do you think it is?
  2. Offline

    ReputationRep:
    There is no substantiate to this question therefore it has no credible answers.

    My personal answer would be 0%. Given whatever the outcome of any number of trials you will never be correct.

    But I am crap at maths
  3. Offline

    ReputationRep:
    It's 50%, but only if you pick a or d...
    omg parad0x.
  4. Offline

    ReputationRep:
    50%...?
  5. Offline

    ReputationRep:
    1/3*1/2 + 1/3*1/4 + 1/3*1/4 = 1/6 + 1/6 = 1/3
  6. Offline

    ReputationRep:
    It isn't any of them. It can't be B or C because the probability of choosing either of those answers is 1/4 which isn't equal to their probabilties. That means it must be A or D. If the answer was 25% then the proability of guessing it correctly is 1/2 which isnt the answer to A or D.
  7. Offline

    ReputationRep:
    nerdgasm !!
  8. Offline

    ReputationRep:
    Picking one answer out of 4 is the same as 1/4 = 25%. Bear in mind that I'm completely retarded.
  9. Offline

    ReputationRep:
    It isnt 50% as there's 3 different options. Where'd 60% come from?

    My head hurts

    But it must be 25% as there's 4 options . . . I dont think having two of them makes any difference :dontknow:
  10. Offline

    ReputationRep:
    My friend who does a2 maths says it's impossible.
  11. Offline

    ReputationRep:
    I'm a total retard when it comes to this kind of stuff, but surely (as the second poster suggested) there is no correct answer because the question posed doesn't have a specific answer in itself.

    A question can only be answered if it actually has an answer. So in order for the posed question to be answerable, there would need to be another question before the posed question. So, for example, let's say that the imaginary first question is 'what is 50% + 10' which would make the answer 60%, which is poll option C. And therefore the answer to the posed question would be that you have a 25% chance of getting the correct answer. But because there are two 25% options (A and D), the answer to the posed question would is 50% (B).

    But if the posed question isn't preceded by a prior question like the one that I have just made up, then it can't be a question in itself, because it can't have an answer. So therefore there is no answer.

    (I have no idea whether any of that made sense, I only managed to scrape a B at GCSE Mathematics)
  12. Offline

    ReputationRep:
    My ex-maths teacher has confirmed that it's impossible.

Reply

Submit reply

Register

Thanks for posting! You just need to create an account in order to submit the post
  1. this can't be left blank
    that username has been taken, please choose another Forgotten your password?
  2. this can't be left blank
    this email is already registered. Forgotten your password?
  3. this can't be left blank

    6 characters or longer with both numbers and letters is safer

  4. this can't be left empty
    your full birthday is required
  1. By joining you agree to our Ts and Cs, privacy policy and site rules

  2. Slide to join now Processing…

Updated: May 15, 2012
TSR Support Team

We have a brilliant team of more than 60 Support Team members looking after discussions on The Student Room, helping to make it a fun, safe and useful place to hang out.

New on TSR

Improving your uni offer

Why now is the time to think about Adjustment

Useful resources
x

Think you'll be in clearing or adjustment?

Hear direct from unis that want to talk to you

Get email alerts for university course places that match your subjects and grades. Just let us know what you're studying.

Quick reply
Reputation gems: You get these gems as you gain rep from other members for making good contributions and giving helpful advice.