Date: 02/28/2002 at 09:12:52 From: Stephen Piggin Subject: Probability - Space Diagrams. Hi there, I am currently studying space diagrams. When there are two or three variables I can often succeed, but I have a complex problem that I cannot figure out. A bag contains 3 blue balls, 1 red ball and 1 white ball. A second bag contains 1 blue ball and 4 red balls. A ball is chosen at random from each bag. Draw a sample space diagram to show the possible outcomes. If you can offer any help it would be appreciated.
Date: 02/28/2002 at 10:35:37 From: Doctor Tim Subject: Re: Probability - Space Diagrams. Hi, Stephen. If I understand what a "space diagram" is, it's analogous to a two-dimensional table. I'll try to render one here in computer characters: First Bag: BBBRW B B B | R | W ---------+----+---- Bb Bb Bb | Rb | Wb | b ---------+----+----+ Br Br Br | Rr | Wr | r Br Br Br | Rr | Wr | r Second bag: brrrr Br Br Br | Rr | Wr | r Br Br Br | Rr | Wr | r ---------+----+----+ So the outcomes are, for example, blue-blue, blue-red, etc. Each of the 25 combinations in the diagram is equally likely (since the balls are chosen at random from each bag). Their probabilities are: blue-blue = 3/25 blue-red = 13/25 (12 Br and one Rb, which should be lumped together if the balls from the different bags look the same) and so forth. I hope this is what you need! - Doctor Tim, The Math Forum http://mathforum.org/dr.math/
Date: 03/01/2002 at 03:02:56 From: Stephen Piggin Subject: Probability - Space Diagrams. Dear Dr. Tim, Thank you so much, it seems so easy now, and I am so pleased I contacted you. Thanks again. Stephen P.S. My Dad says thanks also!
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