I would think this: You have a 1/3 chance of being right Host opens empty door Now lets assume that door has gone away. There are only 2 doors, and you chose one. You still have a 1/2 chnace no matter what the host does. Opening a door didnt change your chances.
Peter Greenwood --- In [email protected], Chris Hunt <[EMAIL PROTECTED]> wrote: > > Ah, sounds like my explanation might be wrong, but at least I pick the right > door :) > > -Chris > > On 12/24/05, Evan Gates <[EMAIL PROTECTED]> wrote: > > > > After you choose a door, the host has to open one. Two out of the three > > times, he has no choice which one to open. When you pick the door at > > first, > > you have a 1/3 chance of being right. After he opens a door, if you stay > > with the door you first chose, you still have a 1/3 chance, if you switch, > > you have a 2/3 chance. There are three possibilities, considering you > > switch doors. > > 1) you were right at first, and you lose > > 2) you were wrong at first, and you win > > 3) you were wrong at first(other door), and you win > > Two out of the three possible outcomes, you win > > > > It also might help if you think of 100 doors instead of 3. > > You choose one door, you have a 1/100 or 1% chance of being right. You > > stay > > with that door while the host opens 98 doors, so you are down to 2, the > > one > > you originally chose, and the last one that he hasn't open. Staying with > > your first choice, you still have a 1% chance. But if you switch, you > > have > > a 99% chance. There is a reason that he hasn't yet opened that door. By > > opening the other ones, he's giving you a clue about where the car is. > > > > and boy do I hope I'm right, because rereading that i sound really > > arrogant lol (really, I'm not and I don't mean to be) ;-) > > -Evan > > > > Until next time, Happy Cubing > > http://www.deepcube.net > > > > > > On 12/24/05, pjgat09 <[EMAIL PROTECTED]> wrote: > > > > > > Hmm, lets see. You start with 3 doors, one with a car. The host > > > cancels out a door giving you 2 doors. That means your guess has a 1/2 > > > chance of being correct. There is no point in changing, its 50-50 no > > > matter what. (unless the game is rigged where the car moves from one > > > door to the next :P ) > > > > > > I would stay with my first choice, though it doesnt matter. Its all > > > personal preferance. > > > > > > Peter Greenwood > > > > > > --- In [email protected], Pedro <[EMAIL PROTECTED]> > > > wrote: > > > > > > > > Ok, this is off topic, but is interesting... > > > > > > > > (please forgive if I make some mistake on the english...) > > > > Suppose you are at a TV show, where you have 3 doors. 1 of the > > > doors has a car, and the other 2 don't have anything. So, the show > > > presenter asks you to choose a door. So, you choose, but he doesn't > > > open your choosen door. He opens an empty door. Then, he makes a > > > question: do you want to continue with your first choice or change to > > > the other door? > > > > > > > > What do you do? > > > > What situation gives you more chances of winning? > > > > > > > > Think about it... > > > > > > > > Pedro > > > > > > > > > > > > --------------------------------- > > > > Yahoo! doce lar. Faça do Yahoo! sua homepage. > > > > > > > > [Non-text portions of this message have been removed] > > > > > > > > > > > > > > > > > > > > > > ------------------------------ > > > YAHOO! GROUPS LINKS > > > > > > > > > - Visit your group "speedsolvingrubikscube< > > http://groups.yahoo.com/group/speedsolvingrubikscube>" > > > on the web. > > > > > > - To unsubscribe from this group, send an email to: > > > [EMAIL PROTECTED]< > > [EMAIL PROTECTED]> > > > > > > - Your use of Yahoo! Groups is subject to the Yahoo! Terms of > > > Service <http://docs.yahoo.com/info/terms/>. > > > > > > > > > ------------------------------ > > > > > > > > > [Non-text portions of this message have been removed] > > > > > > > > > > > > Yahoo! Groups Links > > > > > > > > > > > > > > > > > > > [Non-text portions of this message have been removed] > ------------------------ Yahoo! Groups Sponsor --------------------~--> Get fast access to your favorite Yahoo! Groups. Make Yahoo! your home page http://us.click.yahoo.com/dpRU5A/wUILAA/yQLSAA/MXMplB/TM --------------------------------------------------------------------~-> Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/speedsolvingrubikscube/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
