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You are not logged in. #1 20090717 00:35:20
lost marbles"you know that you do not have Bag B (two black marble)" #2 20090717 01:45:30
Re: lost marblesWelcome, haikoumaths!
Maybe you'll understand the solution better if we list all six possible options.
Why did the vector cross the road? It wanted to be normal. #3 20090717 21:45:58
Re: lost marblesthank you #4 20090717 22:21:46
Re: lost marblesThe bag you selected is either A or C, but their probabilities aren't equal. Why did the vector cross the road? It wanted to be normal. #5 20090718 22:47:42
Re: lost marblesam I splitting hairs? Last edited by haikoumaths (20090718 22:53:17) #6 20090719 00:41:57
Re: lost marbles
The question we really want to answer is Why did the vector cross the road? It wanted to be normal. #7 20111207 05:51:29
Re: lost marblesNot true. The question was "after pulling a white marble what is the probability?" Not, "what is the probability of choosing two white marbles?" The key is when is the question being asked. When it is said that a white marble has been pulled that reduces bag B out of the situation and a white marble out of the remaining bags. So it is down to a 50/50. Everyone has the correct math, just not in line with the wording. The wording eliminates the 1 out of 3 bag chance. #8 20111207 05:58:30
Re: lost marblesIn reply #2 the original question and the rephrase are two different situations. The rephrase actually has the six possible outcomes that are listed above it. The original question by stating a white marble has been pulled, reduces the possible outcomes. Two bags are left with only one marble remaining in each. Since, it wasn't stated that we replace the marble. THis solution needs to be corrected on the site. 