There are 9 marbles in a box: 3 red, 3 white and 3 green. 6 marbles are drawn (a) without a replacement (b) with a replacement.
- Thread starter Gerlya
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What are your thoughts? What have you tried? How far have you gotten? Where are you stuck?
Please be complete. Thank you!
Steven G
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I would try to compute the probability of the 6 balls not containing all 3 colors.
If you want further help, then you should re-read the posting guidelines as your post is not following these guidelines OR follow the advice given by stapel above.
If you want further help, then you should re-read the posting guidelines as your post is not following these guidelines OR follow the advice given by stapel above.
Do you see a peculiar condition - when you draw 6 balls from the 3+3+3 population and NOT have at least one ball of all 3 colors?
pka
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Here is a table of outcomes without replacement.
[imath] R\ W\ G \\ 0\ 3\ 3 \\ 3\ 0\ 3 \\ 3\ 3\ 0 \\ 1\ 2\ 3 \\ 1\ 3\ 2 \\ 2\ 3\ 1 \\ 2\ 1\ 3 \\ 3\ 2\ 1 \\ 3\ 1\ 2 \\ 2\ 2\ 2 [/imath]
Each row adds to six. How rows are there? How many do not contain at least one of each color?
Is each row equally likely? What is the answer to part (a)?
For part (b).with replacement. we need to know how to solve the following.
How many non-negative integers solve [imath]\bf R+W+G=6~?[/imath]
[imath][/imath][imath][/imath]