Sven's Official BrainTeaser Thread !! and Sander.

[TW89]

This was on the film 21 (http://www.sonypictures.com/homevideo/21/) but I didn't understand it lol, but I know the answer  :cursing:

+explain why you think it's wiser to change doors, or to not change doors :dontknow: because I know this one ;)
In fact it isn't really a riddle, it's some kind of mathematical problem, or I don't know how to call it.

^^^And Sven's right.

[Sander]

yes sven is right. and please if you know this one don't tell it. and TW89 i can explain the answer so you'll understand it fully soon (i hope)

[TW89]

S'all good now, I found it on the 'net and understand, but ty.
......Come on someone...

[sputnik]

if we knew the answer we'd all be winning deal or no deal

[Sander]

sputnik it really makes a difference in your winningchance if you change doors or not. but how is the question

[MickyDfreestyle]

you pick a door and change becuase you have a 2/3 chance of picking a goat first time and then if you do you have a 1/2 chance of picking a car?

im not sure if this is good enough explanation its hard to explain XD

[James]

yeh basically the first time u choose u had a 1 in 3  chance of picking it, but once uve pickd it then with the other 2 at least one of them is goin to have the goat in it. if someone shows you the goat, then thers a 50-50 chance of the other being the goat or the prize. so its better to change? i think

[SvenF]

Yes it's better to change. I'm going to call G1 the first goat, G2 the second, and P stands for prize, or whatever is in the last one, which you want to get. Basically, it's like this:

You don't change:
1) You chose G1 and lose.
2) You chose G2 and lose.
3) You chose P and get the prize.
So your chance is 1/3 if you don't change after one door has been opened.

You change:
1) You chose G1 and change. You win.
2) You chose G2 and change. You win.
3) You chose the car and change, you lose.
So your chance is 2/3 if you change after one door has been opened.

In conclusion the chance to win the prize increases by changing.

[TAHA95]

ok this 1 solved,bring the next 1 on

[Sander]

oke sven, you answered correctly although i you knew this one already :cheers: someone feel free to post a riddle, i don't want to wait for answers again now, someone challenge me

[SvenF]

oke sven, you answered correctly although i you knew this one already :cheers: someone feel free to post a riddle, i don't want to wait for answers again now, someone challenge me

I posted the correct answer, because some already posted a half correct answer. :hello:

[TW89]

Ok I'll do one.

What is weightless, can be seen with the naked eye and when you put it in a barrel, it makes the barrel lighter?


And if someone gets it straight away I'll be annoyed lol