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three treasure chests


Guest XplsvBam

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Guest XplsvBam

There are three treasure chests. In one chests there is $400.00. You get to pick 2 times. After the first pick you are shown one of the remaining chests revealing the one (if there are still two) without the prize. Is the probability of getting a prize greater if you stay with your original pick or if you change?

 

 

 

 

 

 

 

(probability discussion)

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are you sure your not talking about the one where there are 3 doors (or chests in this one) and one has a prize in it, and 2 are emtpy, you choose a door, and the person who knows which door the prize is behind opens a door that isn't yours that has nothing in it (since there will allways be a door with nothing behind it no matter which you choose and then gives you the chance to pick which one?

 

 

 

 

 

 

 

because in yours, with 2 prizes you would be guarenteed a prize if 2 of the 3 chests had prizes, and you get 2 picks

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~hawt Knight of the Void~

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Barrows drops: 3. veracs brassard, torags hammers & dharoks greataxe (double drop)

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Your probability of getting a prize is 1 either way.

 

 

 

 

 

 

 

There are three chests, and a prize in two. If you get two picks, worst case scenario your first pick is wrong, and then for the second you're guaranteed a prize.

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For the prizegiver, it's the worst situation (other than just straight out handing out the cash). Your chances of getting at least one prize is 100%, and your chance of getting both is 66.6% (evil). The statistics can't be changed just by changing your pick.

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Guest XplsvBam
For the prizegiver, it's the worst situation (other than just straight out handing out the cash). Your chances of getting at least one prize is 100%, and your chance of getting both is 66.6% (evil). The statistics can't be changed just by changing your pick.
Yea I messed up the situation. Whoops. Its suppose to be only 1 prize.
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I think you're drawing a parallel with this:

 

 

 

 

 

 

 

On a game show there are three curtains. Behind two of the curtains are goats. Behind the other curtain is a Ferrari. The contestant has to choose one of the curtains to open, and he gets whatever is behind that curtain.

 

 

 

 

 

 

 

So Bob the contestant picks a curtain to open. Before it is opened, however, Pat the host opens another curtain, showing the goat behind it. He then gives Bob the opportunity to switch curtains. Should Bob switch?

 

 

 

 

 

 

 

And this is generally where the instructor gets to condemn anyone who says it doesn't matter.

 

 

 

 

 

 

 

When Bob picked the first curtain, there was a 1/3 chance that the Ferrari was behind it, and a 2/3 chance that it was behind another curtain. So it is obvious that if he stays with the curtain he is at there will only be a 1/3 chance of winning the Ferrari. But if he switches, he will have a 2/3 chance.

 

 

 

 

 

 

 

Copied and pasted from another site.

Some people are changed by being a moderator. I wouldn't be.

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Yep a teacher at my college 'condemned me' because i said that it didnt matter. He then went on to 'prove' that it did.

 

 

 

 

 

 

 

However isn't the probably of an event happening the No of ways the event can happen (1) / Total Number of outcomes possible (2)?

 

 

 

 

 

 

 

My main point is that the initial guess is irrelevant to the second, but i can't prove it because my Statistics isn't up to scratch. :oops:

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But if you have one opened up now then there are only 2 possible choices so therefore isn't it a 50/50 chance? :-k

<the49ronin> O_o methinks ard is acting mighty high and pretty -.-

<Ard_Choille> I am pretty

<Ard_Choille> fo shizzle

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Guest XplsvBam
But if you have one opened up now then there are only 2 possible choices so therefore isn't it a 50/50 chance? :-k
yea I don't know where anthesias 2/3 came from.
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But if you have one opened up now then there are only 2 possible choices so therefore isn't it a 50/50 chance? :-k

 

 

 

 

 

 

 

At that moment it's a 50-50, but overall it's a 2/3

 

 

 

 

 

 

 

ok, i see now, btw, how do you like my new siggy?

<the49ronin> O_o methinks ard is acting mighty high and pretty -.-

<Ard_Choille> I am pretty

<Ard_Choille> fo shizzle

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yea I don't know where anthesias 2/3 came from.

 

 

 

 

 

 

 

It isn't mine, it is an actual situation on an actual gameshow that actually happened. There was uproar amongst people who didn't understand why it was 2/3. I remember Mercifull posting on the last thread about it, perhaps he could explain more.

 

 

 

 

 

 

 

The fact is the probability isn't the one you expect it to be. Academics got in slanging matches about it in the media and then it was eventually accepted that it is indeed 2/3 - though on first glance it seems it shouldn't be. What's more, the statistics on the gameshow of who won backed this up.

 

 

 

 

 

 

 

I can't find the wikipedia page on it though.

Some people are changed by being a moderator. I wouldn't be.

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Pfft @ wikipedia explaining it far better than I ever could. lol

 

 

 

Grand Illusionshas a nice page with examples on it too. This simulator is also cool but only works in IE i think http://www.grand-illusions.com/simulator/montysim.htm

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Mercifull <3 Suzi

"We don't want players to be able to buy their way to success in RuneScape. If we let players start doing this, it devalues RuneScape for others. We feel your status in real-life shouldn't affect your ability to be successful in RuneScape" Jagex 01/04/01 - 02/03/12

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The page on Monty Hall explains it well, I too didn't think it was 2/3 at first, but it does make sense. Read it.

 

 

 

 

 

 

 

At the point when the player is asked whether to switch, there are three possible situations corresponding to the player's initial choice, each with equal probability (1/3):

 

 

 

The player originally picked the door hiding goat number 1. The game host has shown the other goat.

 

 

 

The player originally picked the door hiding goat number 2. The game host has shown the other goat.

 

 

 

The player originally picked the door hiding the car. The game host has shown either of the two goats.

 

 

 

 

 

 

 

If the player chooses to switch, the car is won in the first two cases. A player choosing to stay with the initial choice wins in only the third case. Since in two out of three equally likely cases switching wins, the odds of winning by switching are 2/3. In other words, players who switch will win the car on average two times out of three.

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Guest XplsvBam
The page on Monty Hall explains it well, I too didn't think it was 2/3 at first, but it does make sense. Read it.

 

 

 

 

 

 

 

At the point when the player is asked whether to switch, there are three possible situations corresponding to the player's initial choice, each with equal probability (1/3):

 

 

 

The player originally picked the door hiding goat number 1. The game host has shown the other goat.

 

 

 

The player originally picked the door hiding goat number 2. The game host has shown the other goat.

 

 

 

The player originally picked the door hiding the car. The game host has shown either of the two goats.

 

 

 

 

 

 

 

If the player chooses to switch, the car is won in the first two cases. A player choosing to stay with the initial choice wins in only the third case. Since in two out of three equally likely cases switching wins, the odds of winning by switching are 2/3. In other words, players who switch will win the car on average two times out of three.

aww I see, so because of the 2/3 chance of picking the goat originally you have a 2/3 chance of getting a car.
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Guest XplsvBam
Can you explain it a bit better? I mean, why would I stay with my choice?

 

 

 

 

 

 

 

:? Confuzzled.

No don't stay with your choice, by staying with your choice you only have 1/3 chance of getting the prize, but by switching you have a 2/3 chance.

 

 

 

 

 

 

 

2 of the 3 chests doesn't have the money, if on your first pick you choose one of the 2 empty ones and then you switch your choice you are guaranteed the prize.

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2 of the 3 chests doesn't have the money, if on your first pick you choose one of the 2 empty ones and then you switch your choice you are guaranteed the prize.

 

 

 

 

 

 

 

No, you aren't guaranteed the prize.

 

 

 

 

 

 

 

 

 

 

 

he would be if he picked an empty one first, then switched, he would get the prize 100% of the time

 

 

 

 

 

 

 

but how he would know which one is empty is another question....

voidknight.jpg

~hawt Knight of the Void~

image,prof-spc-fleb,white,black.png

Barrows drops: 3. veracs brassard, torags hammers & dharoks greataxe (double drop)

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