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4 replies to this topic

### #1 bonanova

bonanova

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Posted 24 January 2008 - 03:29 PM

Each basket contains 4 balls, indistinguishable except for color.
There is a red, a white, a blue, and a black ball in each basket.
You are blindfolded and asked to remove one ball from each basket.
What are the chances you will pick exactly 2 red balls and 1 non-red ball?
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The greatest challenge to any thinker is stating the problem in a way that will allow a solution.
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### #2 dato

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Posted 24 January 2008 - 03:53 PM

9/64

= 1/4 * 1/4 * 3/4 * 3

Red Red Non-red The number of baskets where the non-red ball can be pulled
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### #3 Jkyle1980

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Posted 24 January 2008 - 09:19 PM

The long way is...

Spoiler for ...

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### #4 PDR

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Posted 25 January 2008 - 02:30 AM

now let's change it...

You are now asked to remove two balls from each basket (ie 6 balls total). Are you more likely to pick exactly [1 red ball and 5 non-red balls] or exactly [2 red balls and 4 non-red balls]? What are the chances?

extra credit - anyone can run the options out the long way (I did ) - but can you explain the math behind the result? I left my high-school math way behind, so don't have a clue what the formula would look like...
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### #5 bonanova

bonanova

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Posted 25 January 2008 - 08:09 AM

Are you more likely to pick exactly [1 red ball and 5 non-red balls] or exactly [2 red balls and 4 non-red balls]?
What are the chances?