Probability riddle

[unoduetre]

Please, do not spoil the fun for other people, if you already know the answer.

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There are 3 closed envelopes with letters on them: A, B and C.

One of them contains a cheque for £1000. The other two contain nothing.

You are asked to choose one envelope.

After making the final decision, you will receive the contents of the envelope (if any).

You've chosen envelope A.

After making the choice, envelope C is opened and it is revealed that it contains nothing.

Now you are given an option to change your initial choice. This will be your final decision.

You can either keep envelope A or switch and keep envelope B.

What should you do and why, assuming you want to maximize the probability that you win the cheque?

a) keep envelope A, because it maximizes the probability that you win the cheque
b) switch and keep envelope B, because it maximizes the probability that you win the cheque
c) it doesn't matter whether you switch or not, the probabilities that you win the cheque are the same for both choices, so you can do either

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Feel free to discuss it with other people in this thread.

[unoduetre]

[mention=113974]Luffynatsu87[/mention] [mention=717]The Grinch[/mention]

What do you think? You can discuss!

[Luffynatsu87]

To be honest depends how look at it i have feeling i know the answer

[PharaohAtem]

To be honest depends how look at it i have feeling i know the answer

Yeah, were probably thinking the same thing.

[unoduetre]

[mention=113974]Luffynatsu87[/mention] [mention=717]The Grinch[/mention]

You can write the answer here. I wonder, if your answers are the same.

[PharaohAtem]

B

[unoduetre]

[mention=717]The Grinch[/mention]

Thanks. Do you want to explain your reasoning?

[mention=113974]Luffynatsu87[/mention]

I wonder what your choice is, but if you don't want to reveal it, that's fine.

[Luffynatsu87]

Mmm i say C as it be like 50p really there 50/50 change it could be either that unless there is clue to what envelope it is in and totally missed it

[unoduetre]

[mention=113974]Luffynatsu87[/mention]

OK, thanks.

I wonder what other people would say. I will reveal the answer after some more people give theirs.

[Beex]

I say B.

Odds are your initial 1 of 3 choice was incorrect.

[unoduetre]

[mention=46027]Beex[/mention]

Thanks for the answer and for the explanation!

I think we need one more person and I will reveal the answer.

[Citizen]

What should you do and why, assuming you want to maximize the probability that you win the cheque?

Do I have a gun in this situation?

This will impact my decision.

[unoduetre]

[mention=1400]Citizen[/mention]

Yes, you have a bazooka with a nuclear missile.

[Citizen]

I wasn't expecting to be that well-armed but I can work with that. Ok so what I do is I leave and sell that for probably a lot more than £1000.

[unoduetre]

[mention=1400]Citizen[/mention]

Sorry, you get arrested, because posession of nuclear weapons by individuals is illegal.

GAME OVER